Nifedipine prolonged action instructions for use. Nifedipine tablets are a potent remedy for normalizing systolic pressure Why nifedipine tablets

14.05.2017

Nifedipine tablets are necessary for hypertensive patients and are a common remedy for pressure , eliminating pain, reducing ischemia.

The drug is produced in several versions:

• adalat - solution for intravenous administration;
• short acting tabletsremove the crisis (cordaflex, nifedipine, cordafen, cordipin, fenigidin);
• long-acting drug that is drunklong-term (cordaflex rd, corinfar, nifecar chl, calciguard retard, osmo-adalat).

Listed medicines for pressure combines the active substance, the mechanism of action on the body and the pharmacological effect. Differ from downgrading AD drugs by the duration of the result obtained, the speed of the onset of the effect from the moment of taking / administering the medication. Given the differences, each form has its own indications, which the doctor must know about.

How does nifedipine affect the body?

Learn more about Nifedipine instructions for use, at what pressureand how to take, what side effects and contraindications. However, it is not necessary to understand medical terminology. The active substance is classified as a Ca-channel blocker. This means that the channels in the cell wall through which calcium enters are blocked.

Many calcium channels in the muscles, including the heart. Penetrating into the cell, calcium provokes excitation, causing a contraction of muscle tissue.

Under conditions of blocking calcium channels, much of it will not enter the cell, which means that the lumen in the vessels will expand, because their walls of their circular muscle fibers will not actively contract under the influence of calcium.

Due to the expansion of the cardiac arteries, blood flow to the myocardium improves, and the increased lumen of distant arteries provides a decrease pressure . The vascular walls relax, the lumen of the veins and arteries increases, the frequency of myocardial contractions succeeds reduce.

Dilated blood vessels, through which blood circulates to the heart and brain, provide blood flow to the main organs, the supply of glucose and oxygen. Against the background of such favorable conditions, cells affected by ischemia and pathologies are poorly restored.

When is Nifedipine prescribed?

pressure medication prescribed for various pathologies, each time selecting the appropriate form of medication:

• as a prophylaxis of angina pectoris in patients with ischemic disease;
• in order to reduce vasospasm in patients with Prinzmetal's angina;
• for downhill pain in the chest if nitroglycerin is not possible accept ;
• to control blood pressure in hypertensive patients in the long term;
• to quickly to stop a hypertensive crisis;
• with Raynaud's syndrome to relieve spasms of distant blood vessels.

An intravenous liquid form of the drug is administered in a hospital if the patient is in serious condition. Short acting tablets fast reduce blood pressure, used in case of an acute attack of angina pectoris and hypertension.

For long-term treatment of hypertension, indicators pressure normalized with prolonged-release tablets.

Dosage of the drug

If the patient has read the instructions and knows what dosagereduces pressure, with hypertension, act according to the principle: “what I want, then I drink ' is dangerous. The doctor can prescribe pills, they act individually for each patient.

The standard daily dosage is 30-80 g. If short-acting tablets are taken, then the daily dose is divided into 3-4 doses, and if long-acting tablets are prescribed, they are taken 1-2 times a day. In case of severe hypertension and variant angina pectoris, the daily dosage can be increased to 120 mg for some time, but as prescribed by the doctor and when the drug is well tolerated. The maximum daily dose is 120 mg.

When you need to remove the pressure surge, put a 10-20 mg tablet under the tongue, which will work for 15 minutes. Do the same for chest pain. In the hospital, an attack of angina pectoris or a crisis is stopped by intravenous administration of Nifedipine in a volume of 5 mg / h, the daily rate is 30 mg.

An overdose of the drug is manifested by facial swelling, headache, prolonged pressure drop, bradycardia, bradyarrhythmia and the absence of a pulse in distant arteries. In case of severe intoxication, loss of consciousness and collapse are possible.

To provide first aid, you need to do a gastric lavage, then prescribe activated charcoal at the rate of 1 tablet per 10 kg of body weight. Nifedipine's drug antidote is calcium; calcium chloride or calcium gluconate in a 10% solution is administered to help the patient.

Adverse reactions

Like other pressure pills, Nifedipine causes side reactions in the body:

• from the gastrointestinal tract: diarrhea, nausea, heartburn and liver failure. If you take the drug for a long time in high doses, this will affect the liver in the form of cholestasis or an increase in transaminases;
• from the side of the cardiovascular system: swelling of the skin and extremities, a strong drop in pressure, a feeling of warmth, asystole, tachycardia, bradycardia, angina pectoris;
• from the side of the central and peripheral nervous system: headaches, with prolonged use, muscle pain, sleep problems, tremors and visual disturbances;
• from the genitourinary system: increased diuresis, against the background of long-term use - failure of the kidneys;
• on the part of hematopoiesis: leukopenia and thrombocytopenia;
• from the endocrine system - a manifestation of gynecomastia.

As an allergy to the components of Nifedipine, a rash on the skin, burning at the injection site is possible. With intravenous administration, an increase in the frequency of myocardial contractions and the development of hypotension are possible.

Contraindications

Nifedipine is not prescribed for hypotension, collapse, severe aortic stenosis, cardiogenic shock, severe heart failure, acute myocardial infarction, tachycardia, minors.

Pregnant and lactating Nifedipine is not recommended, although in gynecological practice there are cases when the drug was necessary in case of ineffectiveness of the drugs. In such cases, the doctor weighs the risks, and may prescribe the drug in late pregnancy in order to stop the hypertensive crisis and normalize the condition of the expectant mother.

In pregnant women, Nifedipine reduces the tone of the uterus, but clinical studies on this issue have not been conducted. It is strictly forbidden for pregnant women to drink the medicine on their own, the decision should be made by the doctor.

A similar appointment with caution applies to patients with diabetes mellitus, malignant arterial hypertension, serious circulatory disorders in the brain, malfunctions of the kidneys and liver.

The effectiveness of Nifedipine

Since the development of the drug, there have been enough international studies on the effectiveness, according to the results, reports have been presented on the benefits, safety and feasibility of prescribing Nifedipine. In 2000, the results of the INSIGHT study were presented, according to which the drug is safe, effectively helps with hypertension, is well tolerated compared to diuretic drugs, and helps reduce the risk of heart attack and stroke in hypertensive patients.

The results of the Action study confirmed the safety of long-acting nifedipine, its ability to reduce the need for coronary artery bypass grafting and coronary angiography. In combination with other drugs, Nifedipine improves the prognosis in hypertensive patients and patients with angina pectoris, including the state after myocardial infarction.

In the recommendations of the European Society of Cardiology there are notes on the positive effect of long-acting nifedipine on the health of patients with stable angina, both in monotherapy and in combination with nitrates and beta-blockers.

Short-term tablets are recommended as a means of emergency care for a hypertensive crisis, if taken for a long time, this is fraught with complications.

Drug Interactions

Before prescribing pills for pressure, the doctor will assess the patient's condition, refer him for diagnosis, select the dosage and regimen of therapy. You need to tell your doctor if you are taking medications, as Nifedipine does not work well with all of them.

The combined use of Nifedipine with diuretics, nitrates, tricyclic antidepressants leads to an accumulation of the effect and an increase in the pressure-reducing effect.

In combination with beta-blockers, the hypotensive effect increases, heart failure develops. Cimetidine together with Nifedipine increases the concentration of the latter in the blood plasma. If you take Rifampicin against the background of Nifedipine, then the metabolism of the latter will accelerate, the effectiveness of its action on the body will decrease.

It is important to consider that long-term treatment of patients with high blood pressure or coronary artery disease is carried out with long-acting drugs. It is valid for 12-24 hours. As for short-term tablets, they should be used as an ambulance for a hypertensive crisis, when you need to effectively and quickly reduce blood pressure.

According to research and practice, if you use short-acting Nifedipine for a long time, this is fraught with a stroke or heart attack.

The doctor selects the dosage of tablets individually in each individual case. Self-treatment, relying on the instructions for the drug - is not worth it, this can lead to dangerous consequences.

Gross formula

Pharmacological group of the substance Nifedipine

Nosological classification (ICD-10)

CAS code

Characteristics of the substance Nifedipine

Calcium channel blocker is a derivative of 1,4-dihydropyridine.

Yellow crystalline powder. Practically insoluble in water, hardly soluble in alcohol. Molecular weight 346.3.

Pharmacology

It blocks calcium channels, inhibits the transmembrane entry of calcium ions into the smooth muscle cells of arterial vessels and cardiomyocytes. Expands peripheral, mainly arterial, vessels, incl. coronary, lowers blood pressure (possible slight reflex tachycardia and increased cardiac output), reduces peripheral vascular resistance and afterload on the heart. Increases coronary blood flow, reduces the force of heart contractions, the work of the heart and myocardial oxygen demand. Improves myocardial function and helps to reduce the size of the heart in chronic heart failure. Lowers pressure in the pulmonary artery, has a positive effect on cerebral hemodynamics. It inhibits platelet aggregation, has anti-atherogenic properties (especially with prolonged use), improves post-stenotic circulation in atherosclerosis. Increases the excretion of sodium and water, lowers the tone of the myometrium (tocolytic effect). Long-term use (2-3 months) is accompanied by the development of tolerance. For long-term therapy of arterial hypertension, it is advisable to use fast-acting dosage forms at a dose of up to 40 mg / day (with an increase in the dose, the development of concomitant reflex reactions is more likely). In patients with bronchial asthma, it can be used with other bronchodilators (sympathomimetics) for maintenance treatment.

When taken orally, it is rapidly and completely absorbed. The bioavailability of all dosage forms is 40-60% due to the "first pass" effect through the liver. About 90% of the administered dose binds to plasma proteins. With intravenous administration, T 1/2 is 3.6 hours, the volume of distribution is 3.9 l / kg, plasma Cl is 0.9 l / min, and the constant concentration is 17 ng / ml. After oral administration, C max in plasma is created after 30 minutes, T 1/2 - 2-4 hours. About 80% is excreted by the kidneys in the form of inactive metabolites and approximately 15% - with faeces. In small quantities, it passes through the BBB and the placental barrier, penetrates into breast milk. In patients with impaired liver function, the total Cl decreases and T 1/2 increases. When capsules are taken orally, the effect manifests itself after 30-60 minutes (chewing accelerates the development of the effect) and lasts 4-6 hours, with sublingual use, it occurs after 5-10 minutes and reaches a maximum within 15-45 minutes. The effect of tablets with a two-phase release develops in 10-15 minutes and lasts 21 hours. It does not have mutagenic and carcinogenic activity.

The use of the substance Nifedipine

Arterial hypertension, including hypertensive crisis, prevention of angina attacks (including Prinzmetal's angina), hypertrophic cardiomyopathy (obstructive, etc.), Raynaud's syndrome, pulmonary hypertension, broncho-obstructive syndrome.

Contraindications

Hypersensitivity, acute period of myocardial infarction (first 8 days), cardiogenic shock, severe aortic stenosis, chronic heart failure in the stage of decompensation, severe arterial hypotension, pregnancy, lactation.

Application restrictions

Age up to 18 years (safety and effectiveness of use have not been determined).

Use during pregnancy and lactation

Contraindicated in pregnancy.

At the time of treatment should stop breastfeeding.

Side effects of the substance Nifedipine

From the side of the cardiovascular system and blood (hematopoiesis, hemostasis: often (at the beginning of treatment) - flushing of the face with a feeling of heat, palpitations, tachycardia; rarely - hypotension (up to fainting), pain similar to angina pectoris, very rarely - anemia, leukopenia, thrombocytopenia, thrombocytopenic purpura.

From the nervous system and sensory organs: at the beginning of treatment - dizziness, headache, rarely - stupor, very rarely - changes in visual perception, impaired sensitivity in the arms and legs.

From the digestive tract: often - constipation, rarely - nausea, diarrhea, very rarely - gingival hyperplasia (with long-term treatment), increased activity of hepatic transaminases.

From the respiratory system: very rarely - bronchospasm.

From the musculoskeletal system: very rarely - myalgia, tremor.

Allergic reactions: itching, urticaria, exanthema, rarely - exfoliative dermatitis.

Others: often (at the beginning of treatment) - swelling and redness of the hands and feet, very rarely - photodermatitis, hyperglycemia, gynecomastia (in elderly patients), burning sensation at the injection site (with intravenous administration).

Interaction

Nitrates, beta-blockers, diuretics, tricyclic antidepressants, fentanyl, alcohol increase the hypotensive effect. Increases theophylline activity, reduces the renal clearance of digoxin. Enhances the side effects of vincristine (reduces excretion). Increases the bioavailability of cephalosporins (cefixime). Cimetidine and ranitidine (to a lesser extent) may increase plasma levels. Diltiazem slows down metabolism (necessary dose reduction of nifedipine). Incompatible with rifampicin (accelerates biotransformation and does not allow creating effective concentrations). Grapefruit juice (large amount) increases bioavailability.

Overdose

Symptoms: severe bradycardia, bradyarrhythmia, arterial hypotension, in severe cases - collapse, slow conduction. When taking a large number of retard tablets, signs of intoxication appear no earlier than after 3-4 hours and can additionally be expressed in loss of consciousness up to coma, cardiogenic shock, convulsions, hyperglycemia, metabolic acidosis, hypoxia.

Treatment: gastric lavage, activated charcoal, the introduction of norepinephrine, calcium chloride or calcium gluconate in atropine solution (in/in). Hemodialysis is ineffective.

Routes of administration

Inside, sublingually, in / in.

Precautions Substance Nifedipine

The drug should be discontinued gradually (possibly the development of a withdrawal syndrome).

Use with caution during work for drivers of vehicles and people whose profession is associated with increased concentration of attention.

special instructions

In patients with stable angina at the beginning of treatment, a paradoxical increase in anginal pain may occur, with severe coronary sclerosis and unstable angina, worsening of myocardial ischemia. It is not recommended to use short-acting drugs for the long-term treatment of angina pectoris or arterial hypertension, because. development of unpredictable changes in blood pressure and reflex angina is possible.

Interactions with other active substances

Trade names

This drug has many benefits. One of them is the possibility of using it both in emergency conditions and in chronic ones. With an attack of retrosternal pain, a tablet of the drug is placed under the tongue and chewed, after which the pain disappears after 5 to 15 minutes. Long-term use of the drug is encouraged in stable exertional angina. In this case, mainly forms of the drug with prolonged action are used.

This drug is convenient to dose, which is extremely important in view of the fact that for each patient the regimen is compiled individually, taking into account the degree of compensation of his disease, as well as the individual characteristics of the organism. In addition, nifedipine is successfully combined with most drugs for many diseases that often accompany the main one. However, it is important to familiarize yourself with the features of parallel drug administration, since some of them can affect the rate of neutralization and elimination of each other.

It should also be noted that nifedipine has long been used in obstetrics as a tocolytic, that is, a drug that reduces the tone of the myometrium - the muscular layer of the uterus. Due to this action, this drug was used for the purpose of terminating a pregnancy with an acute threat of miscarriage. Currently, there are more advanced drugs used for this purpose, with targeted action and less pronounced side effects, but in some cases, nifedipine is preferred due to its effects on the cardiovascular system.

The negative aspects of this remedy come from the positive aspects. In other words, nifedipine is a drug with pronounced physiological effects. If used ineptly, it is likely to do more harm than good, so it should never be used without consulting a doctor.

For patients under 18 years of age, this drug can be prescribed only in exceptional cases, since there is no confirmation of its safety for this category of patients today. In other words, it is not known whether nifedipine will act on the child's body in the same way as an adult or in some other way.

The same dilemma arises for pregnant women. According to some reports, the drug is relatively safe only in the last trimester of pregnancy. In the first two, its use can potentially cause a negative effect on the fetus. However, the degree of such a possibility is little studied, since a negative effect was observed only on animal embryos, and such experiments have not been carried out on humans and are unlikely to ever be carried out.

Due to the fact that the drug penetrates into the secretion of the mammary glands, nursing mothers are advised to transfer the child to artificial feeding for the duration of treatment or resort to the use of other antihypertensive or antianginal agents.

Types of medication, commercial names of analogues, release forms

• dragee;
• tablets;
• solution for intravenous drip.

Nifedipine tablets come in two types - short-acting and extended-release. Short-acting tablets of 10 and 20 mg are mainly used when it is necessary to reduce high blood pressure or get rid of retrosternal pain in rare attacks in relatively healthy patients. In such cases, the use of this drug is episodic. Long-acting tablets are used to compensate ( keeping under control) arterial hypertension and coronary heart disease. This type of medication is more convenient, since the need to take it is reduced from 3 total to 1 time per day. Moreover, such tablets are available in a wide variety of doses from 20 to 60 mg, which allows you to most accurately adjust the treatment of each patient.

The solution for intravenous drip is available in dark glass bottles, 50 ml. The concentration of the solution is 0.1 mg/ml or 0.01%. The scope of its application is exclusively the cardiology department or the intensive care unit, due to the high activity of the drug when administered intravenously.

Nifedipine exists on the pharmaceutical market under the following commercial names:

• Corinfar;
• Cordaflex;
• Nifesan;
• Sanfidipin;
• Nifelat;
• Nifecard;
• Cordipin;
• Nifedicor;
• Nifedex;
• Nifehexal;
• Nifadil;
• Nicardia;
• Adalat and others

Manufacturers of nifedipine

The mechanism of the therapeutic action of the drug

In view of the foregoing, it can be concluded that the bioavailability of the drug ( the ratio of the active substance that has reached its goal to the entire administered single dose) is equal to 40 - 60% on average. The main losses of the drug occur during the first passage through the liver, while most of it has not had time to bind to plasma proteins.

The point of application of this drug is the plasma membrane of muscle cells. Nifedipine blocks the channels for the entry of calcium ions into the cell, as a result of which calcium does not penetrate into it. The chemical reactions responsible for the development of muscle contraction slow down. The most active drug affects cardiomyocytes ( muscle cells of the heart) and smooth muscle of arterial blood vessels. Nifedipine has no effect on the veins, since their muscle layer is poorly expressed. In addition, in medium and large doses, the drug has a strong antispasmodic effect on the smooth muscles of the internal organs. In this regard, nifedipine has been used for a long time in obstetrics and nephrology. In obstetrics - with the threat of miscarriage, due to increased uterine tone, and in nephrology - for the relief of renal colic. To date, there are more advanced drugs used for this purpose, but, nevertheless, in special cases, nifedipine may remain the drug of choice.

The main effect of nifedipine is aimed at:

• heart;
• peripheral vessels.

• negative inotropic ( reducing the force of contraction of the heart);
• negative chronotropic ( slowing heart rate);
• negative dromotropic ( slows down the conduction of nerve impulses along the conduction system of the heart).

However, it should be remembered that when using an excess dose of the drug, especially in subcompensated and decompensated patients, reflex tachycardia often develops ( increase in heart rate) to increase the ejection fraction ( indicator, conditionally designating the efficiency of the heart).

On blood vessels, nifedipine has a single dilating effect, but this leads to many positive effects.

The vasodilating effects of nifedipine are as follows:

• reduction of afterload on the heart, increasing the efficiency of its work;
• elimination of hypertension in the pulmonary circulation - a decrease in shortness of breath due to an increase in the diameter of the bronchi;
• improvement of cerebral circulation;
• improving the excretory function of the kidneys by expanding the renal artery and increasing the excretion of sodium and water ions.

The drug penetrates the placenta, but in small quantities. However, based on this alone, it cannot be concluded that this medicine is harmless to pregnant women. Unfortunately, no studies have been conducted to investigate this issue. Therefore, pregnant women are advised to take the drug, only after consulting with a doctor first. According to clinical observations, its use in the third trimester of pregnancy at standard doses is relatively safe.

Among other things, the active substance passes into the milk of nursing mothers. Its concentration in milk is almost equal to that in blood plasma. Therefore, if it is necessary to use nifedipine, the child must be weaned and fed with artificial nutrient mixtures throughout the treatment. Otherwise, doses that are normal for the mother may be excessive for the child and cause an overdose in his small body with all the complications that follow from this.

Removal of the main part of the drug ( up to 80%) is excreted by the kidneys as inactive metabolites. small part ( up to 15%) is also excreted as metabolites along with the stool. The remaining few percent are removed from the body through sweat, breath, saliva, etc.

The interaction of nifedipine with magnesium salts ( e.g. magnesium sulfate) is also dangerous because of the risk of a sudden drop in blood pressure. In addition, there is a high probability of developing a neuromuscular block, which is expressed by severe weakness, inaccurate movements, shortness of breath, difficulty swallowing, etc. In connection with the foregoing, pregnant women with preeclampsia and eclampsia are primarily recommended to use magnesium sulfate. With a weak effect, the use of nifedipine is contraindicated. Instead, loop diuretics are used ( diuretics such as furosemide, torasemide, etc.), ACE inhibitors ( angiotensin converting enzyme such as captopril, enalaprilat) and other methods, but for a short time. The only way to stop the progression of preeclampsia and eclampsia is through childbirth.

Combined use with digoxin leads to a delayed elimination of the latter, and, accordingly, to the risk of developing bradycardia (heart rate less than 60 / min) and a paradoxical arrhythmogenic (causing arrhythmias) effect.

With the combined use of nifedipine and tacrolimus (an immunosuppressant), the neutralization of the latter in the liver slows down, which leads to its accumulation. In this regard, the dose of tacrolimus must be reduced by 26 - 38% to avoid side effects.

Interaction with phenytoin and carbamazepine is fraught with a decrease in the effectiveness of nifedipine by 70%. In this regard, it is recommended to change nifedipine to an alternative antihypertensive drug from a different pharmacological group.

The use of nifedipine with rifampicin is contraindicated, since the latter increases the activity of liver enzymes, thereby converting almost all of nifedipine during the first passage through the liver.

Approximate cost of medication

The cost of nifedipine in various regions of the Russian Federation

Can nifedipine be taken during pregnancy?

This restriction has a good reason. In the first and second trimester of pregnancy in the body of the fetus, the laying of future vital organs and systems takes place. Any impact, be it a drug, household chemicals, or just stress, can affect the pace and correctness of the processes of division and differentiation ( acquisition of features characteristic of the cells of a particular tissue) fetal cells. In the future, such a mistake can lead to more or less severe anomalies of physical or mental development. For this reason, it is recommended to refrain from all systemic drugs in the first 6 months of pregnancy and use them only when absolutely necessary, when the expected benefit outweighs the potential harm. Topical drugs do not create high concentrations of the active substance in the blood, so they are practically harmless to the fetus.

In the last trimester of pregnancy, the risks of harming the fetus are significantly reduced if the dose is correctly selected for a particular pregnant woman. All vital organs already exist at the moment and are gradually increasing in size.

The annotation to nifedipine states that according to the teratogenicity of the effect ( ability to cause congenital malformations) it belongs to FDA group C drugs ( Food and Drug Administration - US Department of Health Food and Drug Administration). This means that studies have been conducted to study the harm of this drug to the fetus of animals, which confirmed that some harm is still present. In humans, such experiments have not been carried out. Medicines that fall into this category may be prescribed to pregnant women, but only if the expected benefit outweighs the potential harm.

Despite the fact that nifedipine crosses the placenta in very low concentrations and practically cannot harm the fetus, no one undertakes to argue the opposite until special studies are carried out on pregnant women. However, due to the fact that such studies are inhumane, the probability of their implementation approaches zero. Thus, the data that science has to date regarding the safety of nifedipine for pregnant women are unlikely to be replenished in the near future, so you will have to be content with what is.

It is important for pregnant women to remember that nifedipine is not such a harmless drug as, for example, vitamins or nutritional supplements. It has a strong effect on many body systems, so it requires a clear dosage. When accidentally taking a high dose, first of all, blood pressure is greatly reduced. For any person, this threatens to worsen their well-being, up to loss of consciousness due to oxygen starvation of the brain. For pregnant women, the risks are doubled, because at low pressure not only the mother’s body suffers, but also the fetus, which receives less oxygen and nutrients due to poor blood supply to the placenta.

When deciding whether or not a pregnant woman should take nifedipine, one should decide on the purpose for which this drug was prescribed. If the goal is to reduce blood pressure in hypertension, then it would be more correct to choose a drug from another pharmacological group that does not affect the fetus. Such drugs exist, and their choice is quite large. Definitely, the search will not be done by the woman herself, but by her attending physician. In this case, nifedipine can be successfully replaced with diuretics ( furosemide, torasemide, indapamide, spironolactone, etc.), magnesium sulfate, antispasmodics ( drotaverine, mebeverine, papaverine, etc.), sedatives ( valerian tablets, etc.).

If a pregnant woman takes nifedipine to reduce the frequency and intensity of retrosternal pain ( such conditions may well be in young mothers with congenital or acquired heart defects), then nifedipine can certainly be replaced with nitro drugs such as isosorbide dinitrate ( kardiket), isosorbide mononitrate ( allowed only in the second and third trimester) and etc.

With the threat of preterm labor, nifedipine can be used, but only in the last trimester of pregnancy. It is preferable that this drug be used in low doses and in complex therapy with other drugs that reduce uterine tone. There are also plenty of such resources. The most prominent representatives are antispasmodics ( baralgin, papaverine, drotaverine, mebeverine, etc.), agents that reduce uterine activity ( magnesium sulfate, magnesium B-6, etc.), beta adrenomimetics ( partusisten, terbutaline, etc.).

Summing up the above, it should be noted that nifedipine is not an indispensable drug for pregnant women. If necessary, its effects may well be replaced by one or a combination of drugs, depending on which of its effects is needed in the treatment.

Can Nifedipine be taken while breastfeeding?

When it enters the human body, this drug is evenly distributed in all tissues and organs, with the exception of the brain, since it is not able to overcome the blood-brain barrier. However, in people who have suffered a serious traumatic brain injury in the past or suffer from certain mental illnesses, this barrier may be weakened. This promotes the penetration of more drugs into the brain, which often causes side effects from the central nervous system.

So, distributing throughout the body, nifedipine enters the mammary glands and directly into their secret - breast milk. Given that bioavailability ( the proportion of the substance that has an effect on peripheral tissues in relation to the total administered dose) of this medicine is equal to 40 - 60% in the body of a child through milk can enter with one average feeding ( 100 - 200 ml) from 1:40 to 1:80 of the adult dose. Considering that the weight of a child is less than the weight of an adult by an average of 10-15 times, such a dose may seem relatively small for the manifestation of the clinical effect of nifedipine in a child. However, it is not.

In the womb, the child prepares for the transition to the outside world, and its internal organs develop just enough to endure this transition. Their further growth and development occurs after birth for at least 25-28 years. However, the most significant changes are observed in the first year of life. During this period, the tissues of the baby are extremely sensitive to any kind of biological and chemical signals. Therefore, the dose of nifedipine, which by all accounts, when taken with milk, should be too small for a child, is actually too high.

Overdose leads to two types of side effects - short-term and long-term ( permanent). The first type are short-term side effects, which by all indications are similar to the symptoms of an overdose in an adult.

The short-term side effects of nifedipine on the infant's body are presumably:

• decrease or compensatory increase in heart rate;
• lowering blood pressure;
• cold extremities;
• blue nasolabial triangle;
• cold and clammy sweat;
• decreased muscle tone;
• severe lethargy of the child;
• loss of consciousness
• seizures, etc.

The persistent side effects of nifedipine on the baby's body are presumably:

• tachycardia ( heart rate higher than normal(60 - 90 beats per minute));
• increased blood pressure in relation to age standards;
• lagging behind in physical development short stature, low muscle mass, etc.);
• the formation of acquired heart defects;
• exacerbation of congenital heart defects;
• blockade at various levels of the conduction system of the heart ( a system that ensures the correct sequence of contraction of various parts of the heart);
• rarely - mental retardation, etc.

Neurological symptoms in children are:

• headache;
• a state of stupor;
• lethargy;
• unreasonable crying, etc.

Advantages and disadvantages of replacing nifedipine with other drugs

To lower blood pressure in nursing mothers, instead of nifedipine, the following can be used:

• furosemide;
• torasemide;
• indapamide;
• spironolactone;
• magnesium sulfate;
• drotaverine
• valerian ( tablets) and etc.

Advantages and disadvantages of transferring a child to artificial feeding during treatment with nifedipine

Which of the analogues of nifedipine is better?

In practice, there are indeed cases when the same active substance in different medicines from different manufacturers has a different effect in strength. As a rule, in this case we are talking about original drugs and generic drugs. Original drugs are those drugs that were first invented, patented and put into mass production by one of the pharmacological companies. Generic drugs are copies of the original drug, and not always quite successful. It follows from this that original drugs are better than generics. However, this statement is true only during the first 10-20 years since the invention of the drug.

The explanation for this phenomenon is as follows. Together with the invention of a new medicinal substance ( original drug) a pharmaceutical company acquires a patent and copyright for this drug. As a rule, according to this contract, none of the competing pharmaceutical companies has the right to put on the market an analogue of the original drug, called a generic, within 5 to 10 years from the date of registration of the patent. This time is provided by the state to the company that developed the drug in order to recoup the amount spent on research in this area. After this time, the copyright expires, and the pharmaceutical company that developed the drug is forced to reveal the formula of the drug and how it is produced to the world. However, in practice, only the main points of production are disclosed, and the first pharmaceutical company reserves some of the secrets, since this brings financial benefits. In order to bring the process of manufacturing generic drugs to the level of the original drug, some more time is required, on average another 5-10 years.

Thus, the following picture is obtained. The first 5-10 years, the original drug has no equal. The second 5 - 10 years, the original drug has copies that differ in quality. And only after a total of 10 - 20 years, generic drugs are equalized in quality with the original drug.

Original drugs, even after 20 years, usually retain their original cost, which is a kind of marketing ploy. Consumers continue to think that if a drug is more expensive, then it is better. However, in practice, in the case of nifedipine, the situation is different. More than 20 years have passed since its invention, and therefore all analogues of this drug do not differ in quality from the original. Therefore, when buying this product, it makes sense to save money and buy a less expensive product, since it will not be inferior in quality to the original.

There is still a possibility that the pharmacy will sell the patient a completely counterfeit drug, which, in fact, is not nifedipine. At best, instead of the active substance, there will be a placebo, and at worst, any other chemistry. However, counterfeiting nifedipine is not particularly profitable due to the fact that the price of this drug is quite low and will not bring big profits. In addition, a patient with a history of hypertension or coronary heart disease will immediately identify a fake, because he knows how the effect of this medicine should manifest itself, and, as a result, next time he will not buy a fake drug.

The risk of buying fake nifedipine is minimal today. Nevertheless, in order not to become a victim of a low-quality drug, it is recommended to buy medicines in large and time-tested pharmacy chains. These pharmacies work with regular suppliers and double-check medicines in order to prevent marriage and not lose reputation.

All of the above applies only to the tablet dosage form of nifedipine. These mechanisms do not apply to solutions for intravenous injections, since there is only one brand on the Russian market called Adalat. In other words, the problem of choosing the best analogue among nifedipine solutions disappears by itself, since this choice simply does not exist.

Do I need a prescription to buy nifedipine?

A prescription is a legal document that holds a physician responsible for the effects of a particular drug prescribed by him to a particular patient. For a pharmacist, a prescription is also a kind of evidence that the patient is buying the drug not for his own reasons, but only after consulting a doctor. In the event that litigation arises between the doctor and the patient, the prescription can become a document that determines the guilt of one or the other party.

However, the legal aspects of the application of prescriptions are left aside when it comes to the health of the patient. Nifedipine is a strong drug in terms of its clinical effect. It should be dosed by a specialist, and not by the patient himself, since otherwise there is a risk of overdose. In some cases, an overdose of this drug can cause irreparable damage to the patient's health. In severe cases, it can be fatal.

Symptoms of an overdose of nifedipine are:

• occurrence of cardiac arrhythmias;
• signs of low blood pressure weakness, dizziness, nausea, cold and sticky sweat, etc.);
• loss of consciousness;
• paradoxical chest pains ( Normally, the drug relieves such pain);

• decrease in the force of cardiac contraction;
• decrease in the speed of nerve impulse conduction along the conduction system of the heart;
• decrease in heart rate;
• expansion of arterioles, due to the relaxation of their smooth muscle membrane.

Due to the fact that nifedipine, as mentioned above, produces a strong clinical effect, it has serious contraindications and restrictions for use in some groups of patients. For example, according to some data, the drug is completely contraindicated for pregnant women, and according to others, only in the first and second trimesters. For nursing mothers, this drug is prescribed only for health reasons. Children and young people under 18 years of age, this drug is not prescribed at all, since there is no evidence of its harmlessness for this category of patients today. For patients with decompensated heart failure, the drug is absolutely contraindicated.

The doctor knows these features of the drug and will not write a prescription for its purchase if nifedipine could potentially harm the patient or the fetus in the womb. Patients do not always know these features and therefore risk causing manifestations of side effects of the drug. As a result, we can conclude that having a prescription for the purchase of nifedipine in hand, the patient automatically falls into the category of patients for whom nifedipine is not contraindicated.

In practice, the situation is somewhat different. You can buy this drug without a prescription without any problems in almost any pharmacy. Pharmacists behind the counter often neglect the lack of a prescription in favor of profit, since the pharmaceutical business is one of the most profitable in the world, and the competition in it is quite high.

It is much easier for the patient to ask friends, neighbors, colleagues who had similar symptoms what they took to eliminate them than to make an appointment with a doctor, wait a certain time and get qualified help. Thus, the patient comes to the pharmacy, buys the first analogue of nifedipine that comes across among the numerous types and asks the pharmacist how to take it. At best, the pharmacist will suspect something is wrong and will not sell the drug without a proper prescription. In the worst case, the pharmacist gives the patient a standard regimen for taking nifedipine, not having the slightest idea about what disease this patient has and whether he needs the drug in principle. In addition, the pharmacist does not know what other drugs the patient is taking, which is certainly important in light of the fact that nifedipine can create highly undesirable combinations with certain cardiac drugs. As a result, all risks remain solely with the patient. In the event of a negative effect from taking the drug, the patient has no one to recover from except himself.

After all of the above, it is worth concluding that a prescription for the purchase of nifedipine is extremely important, even if the patient has taken it all his life and knows its effects and the required dosage. Such precautions are carried out, first of all, for the benefit of the patient himself.

Can nifedipine be given to children?

A child's body is very different from an adult's body. This fact is easily confirmed by various age norms of physiological indicators of the body.

The following physiological parameters normally vary at different ages:

• heart rate;
• arterial pressure;
• leukocyte formula ( percentage of different types of white blood cells);
• hormonal profile;
• amplitudes of brain wave oscillations during various activities and much more.

As you know, medicine is a science based on evidence. To use this or that medication, it is necessary to conduct numerous studies confirming the effectiveness of this drug, as well as its harmlessness, including in the long term. In the case of nifedipine, it was not possible to study its effect on the body of children. In order to achieve this goal, when testing the drug, it is necessary to expose a group of children to an undefined risk. In civilized countries, where almost all pharmaceutical research in the world is carried out, these studies will never be carried out for reasons of humanism and ethics. In connection with the foregoing, it remains unknown how the child's body will react to taking this medication once and for a long time.

Hypothetically, it can be assumed that a single dose of the lowest dose of nifedipine in a patient approaching the age of 18 years will have the same effects as in an adult. However, as the age of the patient decreases and the duration of the drug intake increases, its effects will become more and more unpredictable.

According to one hypothesis, after a few months of using this drug, the body's tolerance to this drug will come, as it happens in adults, but much faster. In other words, the body will get used to a certain dose and to achieve the effect it will have to be increased over and over again. However, with a sharp cessation of the use of the drug, a withdrawal syndrome will occur ( rebound), manifested by the return of the previous symptoms, but with a more pronounced clinical manifestation.

According to another hypothesis, the use of nifedipine for more than several years in a row in childhood can affect the correct growth of the heart as an organ, as well as disrupt the blood pressure self-regulation system.

As a result of such an influence, the following deviations may form in the child's body:

• sinus tachycardia ( heart rate above 90 per minute);
• persistently elevated blood pressure by more than 10 - 20 mm Hg in relation to normal values ​​( 140/90 mmHg Art.);
• lagging behind in physical development due to a decrease in the pumping function of the heart;
• mental retardation;
• the appearance of acquired and aggravation of congenital heart defects;
• complete and incomplete blockade of the conduction pathways of the heart, etc.

Can I drink alcohol while taking nifedipine?

Nifedipine lowers blood pressure by relaxing the smooth muscles in the walls of peripheral blood vessels. The relaxation of the walls occurs due to a decrease in the rate of entry of calcium ions into the muscle cell.

Alcohol lowers blood pressure in other ways. First, it leads to a slowdown in neuromuscular transmission, due to which a drunk person develops some instability and loss of coordination of movements. However, this effect plays a small role in blood pressure regulation. Secondly, alcohol affects the central nervous system as well as the autonomic nervous system.

The effect of alcohol on the nervous system is carried out in several stages. According to various sources, these stages exist from two to five. However, for ease of understanding, only two steps will follow. The first stage is euphoric. In other words, for 15 - 30 minutes after drinking alcohol ( for some, this time can be both shorter and longer) the mood of a person rises, all problems seem insignificant and distant, fears decrease. In people with mental illness, this stage is often absent, and it is replaced by irritability, aggressiveness, and cheeky behavior. The second stage is the stage of inhibition of the cortical processes of the brain. It is manifested by a decrease in mental abilities, relaxation, decreased coordination and, ultimately, falling asleep.

Both in the first and in the second stage of the action of alcohol, its effect on the body is also ensured through the autonomic nervous system. The autonomic nervous system is not controlled by desires. It is responsible for all reflex reactions that occur in the body, developed over many centuries of evolution and designed to ensure human survival in various environmental conditions. These reactions include dilation and constriction of the pupils, sweating, regulation of heart rate and blood pressure, the work of the glands of internal and external secretion, trembling in the cold, and much more.

The autonomic nervous system is divided into two parts:

• sympathetic nervous system;
• parasympathetic nervous system.

parasympathetic nervous system has an opposite effect on the body, i.e., it calms, lulls, reduces the heart rate, etc.

These systems are in constant interaction, and the state of a person at a particular point in time depends on the tone of each of them. In the euphoric stage of alcohol intoxication, the influence of the sympathetic nervous system prevails, and in the second stage, the inhibitory one, the influence of the parasympathetic system increases. Moreover, it is important to note that alcohol greatly potentiates the influence of the parasympathetic system, resulting in an early falling asleep, accompanied by a decrease in blood pressure.

Thus, while taking nifedipine and alcoholic beverages, their actions are superimposed on each other and summarized. As a result, the decrease in blood pressure occurs faster and more pronounced. The heart rate, contrary to expectations, does not decrease, but increases, as a compensatory response to a strong decrease in blood pressure.

With severe alcohol intoxication and taking an average or large single dose, there is a high probability of developing a collapse ( decrease in blood pressure to zero values), cardiogenic shock, acute myocardial infarction. These conditions are critical and in a fairly large number of cases lead to death.

What if I have a headache after taking nifedipine?

It should be noted that such pain occurs mainly when taking nifedipine under the tongue or intravenously. When taking pills inside, the pains appear less often and are less painful. The reason for this difference is the speed of onset of the effect, which is maximum when administered intravenously, average when taken under the tongue, and minimal when taken orally.

Mechanism of action of nifedipine
The point of application of the effect of nifedipine is muscle tissue. In particular, this drug most actively affects the heart muscle and the muscular membrane of peripheral vessels. When exposed to the heart, the vessels that feed it dilate ( coronary arteries), the rhythm slows down, the strength of each individual contraction decreases, the speed of the impulse through the conduction system of the heart decreases slightly. Thus, the supply of oxygen to the heart muscle increases and the rate of work of the heart decreases, allowing it some rest. Through the same mechanism, retrosternal pain caused by ischemia disappears ( insufficient blood supply) myocardium ( cardiac muscle).

The effect of nifedipine on the muscle layer of the vascular wall leads to its relaxation and, as a result, to an increase in the diameter of peripheral arteries. However, it should be noted that this effect extends only to arteries of various calibers, since their muscle layer is much thicker than that of veins. Expansion of peripheral vessels leads to a decrease in systemic arterial pressure. A decrease in blood pressure to some extent reduces the afterload on the heart, also reducing the intensity of its work.

Mechanism of headache
As mentioned above, the decrease in blood pressure when using nifedipine is due to the expansion of peripheral vessels. The blood vessels of the head also dilate. With their sharp expansion, pain occurs. The occurrence of pain is the result of two mechanisms.

In the first case, the expansion of blood vessels leads to their stretching, which is signaled by baroreceptors ( pressure receptors) vessel walls. With a sharp expansion, this impulse becomes more frequent, which is interpreted by the brain as pain.

In the second case, pain occurs as a consequence of the so-called "steal" phenomenon. Since the brain is located above all other organs, with a sharp decrease in blood pressure, for some time the brain receives less oxygen, since it is poorly supplied with blood. During this time, decay products accumulate in it and oxygen is not supplied, which together causes severe pain. As the blood supply to the brain improves, the pain subsides.

Advantages and disadvantages
Undoubtedly, a headache when using nifedipine is far from the most pleasant feeling. However, on the other hand, it is not fatal, especially considering that it goes away on its own in 15 to 30 seconds. Pain is evidence that the drug is working.

If pain and some other unpleasant moments of using nifedipine are placed on one side of the scale, and the negative effect caused to the body by hypertension or myocardial ischemia is placed on the other ( for example, due to stable angina or atrial fibrillation), it will definitely become clear that the latter is much more dangerous. Therefore, you should not give up nifedipine because of headaches. These pains do not have a significant negative effect on the brain and are quite a reasonable price for saving the patient's life in some critical situations.

What should I do if my child accidentally takes nifedipine?

An overdose of nifedipine is quite easy to allow, without knowing the regimen and the exact dose to be taken. In addition, some medications taken concomitantly can slow down the excretion of nifedipine from the body, lead to its accumulation and, ultimately, to an overdose.


Among the medicines that, when taken in parallel with nifedipine, can cause an overdose of it, include:

• cimetidine;

If, after taking the pill, parents do not notice changes in the child's condition for one or two hours, then this is not at all a reason for reassurance. Recently, nifedipine is being produced more and more often in the form of tablets coated with a special film coating, which provides a longer effect of the drug. Such tablets begin to act 2 hours after swallowing or more.

It is important to note that nifedipine is available in the form of a large number of analogues, each with its own commercial name. However, this should not mislead parents, since the active substance in them remains the same and still has a negative effect on the child's body.

Commercial(trading)the names of nifedipine are:

• adalat;
• calciguard retard;
• cordafen;
• cordaflex;
• cordipin;
• corinfar;
• nicardia;
• nifadil;
• nifebene;
• nifehexal;
• nifedex;
• nifedicap;
• nifedicor;
• nifecard;
• nifelate;
• nifesan;
• sanfidipin;
• fenigidin, etc.

• dizziness;
• severe weakness;
• pallor and cyanosis of the skin;
• causeless crying;
• decrease, and then a compensatory increase in heart rate;
• lowering blood pressure;
• dyspnea;
• loss of consciousness;
• convulsions.

First aid

Action algorithm

• Independently, with the help of relatives or an outsider, call an ambulance. Clearly explain to the dispatcher that the child was poisoned by pills and briefly describe his condition (conscious or not, vomiting, convulsions, etc.). This description automatically marks the call with a red code, which guarantees the arrival of a pediatric intensive care unit, a simple resuscitation, or the nearest available team as soon as possible.
• If the child is unconscious, then it must be laid on its side to prevent blockage of the airways by vomit or tongue. Place an emphasis (pillow, bundle of any fabric) under the neck and head. The head should be at a level with its physiological position. In this position, you should wait for an ambulance. It will not be possible to provide other assistance without special training and tools to the child.
• If the child is conscious, then you should immediately tilt it forward and press on the root of the tongue until vomiting occurs. Regardless of whether tablets were present in the vomit or not, the child should be given plain water to drink and vomiting should be repeated. This procedure must be continued until clean water appears in the vomit.

Prevention measures

• keep all drugs out of reach of children;
• as they grow older, children should be taught that drugs can cause great harm if they are used ineptly;
• store highly dangerous drugs ( affecting the brain, cardiovascular system, kidney and liver function, etc.) in a separate place unknown to the child.

Nifedipine has been used since the 1970s to treat hypertension and cardiovascular disease. These tablets belong to the group of calcium antagonists (calcium channel blockers). Until now, nifedipine remains one of the most “popular” drugs in cardiology, that is, doctors prescribe it very often. Nifedipine has become an even more sought-after drug since the introduction of 24-hour tablets of the drug in the 2000s. They can be taken once a day, and not 2-4 times a day, as it was before.

There are fast-acting nifedipine tablets, as well as "extended" dosage forms. Long-acting nifedipine begins to act later, but it lowers blood pressure smoothly and for a long time, i.e. for 12-24 hours.

Since 1998, articles began to appear in medical journals that fast-acting nifedipine increases the overall mortality of patients, as well as the incidence of heart attacks and strokes. This means that only long-acting nifedipine tablets are suitable for long-term treatment of hypertension and coronary heart disease. The most popular of these are OSMO-Adalat and Corinfar UNO, which we will discuss in detail below in the article. Rapid-acting nifedipine is only suitable for the relief of hypertensive crises. Unfortunately, few patients and doctors know about this. Hundreds of thousands of people continue to be treated regularly. Patients - if you want to live longer, then use extended-release nifedipine tablets, not “fast” ones.

Nifedipine - instruction

This article consists of instructions for nifedipine supplemented by information from domestic and foreign medical journals. The official instructions for the use of nifedipine tablets for pressure and for the treatment of heart problems are written in detail, but not too clear. We have tried to provide information conveniently so that you can quickly find answers to questions that interest you.

Instructions for the drug nifedipine, as well as any other materials on the Internet or in print publications, are intended for specialists. Patients - do not use this information for self-treatment. The side effects of self-medication with nifedipine can be harmful to your health, even fatal. This drug should only be taken as directed by your doctor. The instructions for nifedipine contain an extensive list of side effects of this medication. Doctors in practice know that these side effects are observed very often.

Separately, it is worth noting that it is almost impossible to choose the dosage of nifedipine on your own. It will either be too low or too high. In both cases, there will be no benefit from taking the pills, but only harm. Therefore, treatment with this drug should only take place under the supervision of an experienced qualified doctor.

Indications for use

The main indications for the use of nifedipine are hypertension (arterial hypertension), as well as angina pectoris in patients who suffer from chronic coronary heart disease. Nifedipine belongs to the group of calcium antagonists, derivatives of dihydropyridine. In accordance with all international recommendations, drugs in this group are included in the list of drugs for hypertension of the first choice, that is, the main ones.

Additional indications for the appointment of nifedipine:

advanced age of the patient; isolated systolic hypertension; atherosclerosis of peripheral arteries (in the legs) and / or carotid artery; pregnancy.

Pregnancy is one of the important indications for the use of nifedipine. Dihydropyridine calcium antagonists are considered more or less safe drugs for the treatment of hypertension in pregnant women. Do not self-medicate hypertension during pregnancy with nifedipine. Below in this article we will discuss in detail the topic “Nifedipine during pregnancy”.

Contraindications

Contraindications to the appointment of nifedipine are:

hypotension (excessively low blood pressure); cardiogenic shock; hypersensitivity to the drug.

It is not recommended to prescribe this medicine for unstable coronary heart disease, after myocardial infarction.

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Side effects

Nifedipine does not adversely affect the level of cholesterol and uric acid in the blood. The most common side effects of this drug are:

swelling of the legs; headache; skin redness; dizzy heartbeat (tachycardia).

Back in 1982, the results of a large-scale study of the side effects of nifedipine were published, in which more than 3 thousand patients took part. Of these patients, 2147 had severe angina resistant to treatment with beta-blockers and nitrates at normal doses. Therefore, the range of dosages of nifedipine that were used was wide - from 10 to 240 mg per day. Patients were prescribed nifedipine tablets, which act quickly, but not for long, since prolonged forms of this drug had not yet been invented.

It turned out that nifedipine had side effects in almost 40% of patients:

dizziness - 12.1%; swelling in the legs - 7.7%; feeling hot - 7.4%; complaints from the gastrointestinal tract - 7.5%; increased angina - 1.2%.

Modern dosage forms of nifedipine are much better tolerated than previous generation short-acting tablets. Most of the side effects of nifedipine are due to the fact that this drug has vasodilating properties, that is, it “relaxes” the blood vessels. Because of this, unpleasant symptoms occur, which were listed above. The side effects of nifedipine are very dependent on the dosage and on whether the concentration of the active substance in the blood “jumps” a lot. Therefore, with the advent of long-acting nifedipine tablets, patient complaints about side effects have decreased several times.

If you use nifedipine in its usual form (quick-acting), then the frequency of side effects reaches 33.3-58.5%. Nifedipine retard is a nifedipine that lasts 12-16 hours and needs to be taken 2 times a day. It has side effects in 16.3-22.7% of cases, according to various studies. And the newest 24-hour nifedipine (OSMO-Adalat, Corinfar UNO and other competing tablets) causes side effects in 9.7-31.7% of cases, depending on which particular drug is used. Read also "About the dosage forms of nifedipine - in detail."

To improve tolerability and eliminate unwanted effects, it is advisable to combine nifedipine with beta-blockers or antihypertensive drugs from other groups. For more information, read the note "Treatment of hypertension with combined drugs." If edema appears as a result of taking nifedipine, then when treatment is discontinued, they most often quickly disappear.

Nifedipine and other calcium antagonists

Nifedipine belongs to the calcium antagonist group of dihydropyridine derivatives. Two other subgroups of calcium antagonists are the benzothiazepines (dilthiazem) and the phenylalkylamines (verapamil). Medicines of the dihydropyridine group have the following advantages:

more pronounced ability to relax blood vessels; there is no effect on the function of the sinus node of the heart and atrioventricular conduction; reduced ability to inhibit the contractility of the left ventricle of the heart.

These differences largely determine the features of the practical application of dihydropyridine calcium antagonists in general and nifedipine in particular.

What are the dosage forms of this drug

The efficacy and safety of the use of nifedipine to a large extent depends on the dosage form in which the patient takes it. Rapid-acting nifedipine tablets and capsules have been used since the 1970s. In the late 1990s, extended dosage forms appeared. Nifedipine, which sharply lowers blood pressure and is rapidly eliminated from the body, is less effective and less well tolerated than one that works smoothly for 12-24 hours.

The action of nifedipine depends on how much its concentration in the blood fluctuates, how quickly it rises and falls. Conventional nifedipine tablets differ in that they sharply lower blood pressure. In response to this, a reflex release of adrenaline and other “stimulating” hormones occurs. These hormones can cause tachycardia (palpitations), headache, feeling hot, and redness of the skin. Since short-acting nifedipine is rapidly eliminated from the body, a “rebound” phenomenon may occur. This means that sometimes blood pressure jumps even higher than it was before taking the pill.

What other disadvantages do “fast” dosage forms of nifedipine have:

they need to be taken several times a day, which is inconvenient for patients, and therefore patients often refuse treatment; the effect of drugs is not stable during the day and changes due to meals; these pills act very differently on different people, depending on genetic characteristics, age and preservation of kidney function; under the influence of these drugs, blood pressure fluctuates like a roller coaster, which is why atherosclerosis rapidly develops in the blood vessels.

Currently, "fast" nifedipine is recommended only for the relief of hypertensive crises. It is not intended for long-term treatment because it does not improve or even worsen the long-term prognosis for patients. Long-acting nifedipine is suitable for continuous use in hypertension and cardiovascular diseases.

Extended form and its benefits

Dosage forms of nifedipine of prolonged action provide a slow flow of the active substance into the blood. Peak levels of nifedipine in the blood are much lower than if you use fast-acting tablets. At the same time, blood pressure decreases for a period of 12-24 hours and much more smoothly. Therefore, there is no reflex release of “stimulating” hormones into the blood. Accordingly, tachycardia (palpitations) and other side effects of nifedipine are observed several times less often and are less pronounced. Long-acting forms of nifedipine are not effective for the relief of a hypertensive crisis. But they rarely have negative side effects and, most importantly, improve the long-term prognosis for patients.

Characteristics of "extended" dosage forms of nifedipine

The original preparation of nifedipine was developed by the German company Bayer AG and was called Adalat. In the form of fast-acting capsules, it is no longer available. Currently on the pharmaceutical market are:

Adalat-SL - valid for 12-16 hours, prescribed for admission 2 times a day; OSMO-Adalat - maintains a stable concentration of nifedipine in the blood for more than 24 hours, is prescribed 1 time per day.

OSMO-Adalat is a dosage form of nifedipine with a significantly prolonged action. It is called GITS or GITS - Gastrointerstitial (Gastrointestinal) Therapeutic System. It has the most favorable effect due to its ability to maintain a uniform concentration of nifedipine in the blood.

Prolonged tablets of nifedipine act 12-24 hours and are prescribed 1-2 times a day. Their pharmacokinetics are independent of food intake. Osmo-Adalat and Corinfar Uno are the most popular nifedipine preparations, because with a single dose they provide a more or less stable concentration of the drug in the blood for a whole day. This increases the effectiveness of treatment, reduces damage to target organs (heart, kidneys, eyes, and others), and reduces the frequency of complications of hypertension. In addition, patients are more willing to be treated with pressure pills, which are enough to take once a day.

Attention! Nifedipine extended-release tablets require special handling. They cannot be crushed, dissolved or absorbed in the oral cavity. These medicines should be swallowed immediately with water. It is forbidden to divide a tablet in order to reduce the dosage, unless the instructions say that you can do this.

Analogies and synonyms of nifedipine

Nifedipine (adalat, cordafen, cordaflex, corinfar, cordipin, nicardia, nifebene, procardia, farmadipine, fenigidin, etc.) is available in tablets and capsules of 10 and 20 mg, farmadipine - in drops. Prolonged forms - adalat-SL, Corinfar Uno, Corinfar-retard, cordipin-retard, nifebene-retard, nifedipine SS and others - are available in slow-release tablets of 20, 30, 40, 60 and 90 mg. As you can see, there are almost two dozen synonyms for nifedipine. Many pharmaceutical companies produce fast-acting and extended-release nifedipine analogues because this drug is in high demand.

To choose the most suitable pills among all nifedipine analogues, you need to figure out what is the difference between a "short" and "extended" drug. To do this, read "What are the dosage forms of nifedipine".

Short-acting nifedipine is no longer recommended for the long-term treatment of hypertension and cardiovascular disease. It is recommended to take it only for emergency care for hypertensive crises. Nevertheless, in the CIS countries it still accounts for more than half of sales. A cheap, fast-acting drug is most often produced in tablets, which are called nifedipine. For example, nifedipine-Darnitsa.

Nifedipine with a gastrointestinal therapeutic system (GITS or GITS) is produced under the name OSMO-Adalat in capsules with a special membrane, through the hole in which the drug is gradually released over 24 hours. In this regard, it can be prescribed once a day, like Corinfar Uno .

Nifedipine for pressure

As tablets for pressure, 3 subgroups of drugs from the class of calcium antagonists are used:

phenylalkylamines (verapamil); benzothiazepines (diltiazem); dihydropyridines, which include nifedipine.

Dihydropyridine calcium antagonists (amlodipine, isradipine, lercanidipine and the most popular among them nifedipine) are most often prescribed for pressure. Because they are characterized by a minimal effect on the conduction function of the heart and the function of the sinus node. Also, these drugs relax the blood vessels well.

In 1995, articles began to appear in American medical journals that nifedipine in the treatment of hypertension did not improve, but even worsened the prognosis for patients, i.e., increased the likelihood of a heart attack or stroke. Later studies showed that this only applies to fast-acting nifedipine tablets. Long-acting nifedipine dosage forms are useful for lowering blood pressure, improve prognosis and are well tolerated by patients. Nifedipine retard, which lasts 12-16 hours, has confirmed its effectiveness, and even better - nifedipine in the form of GITS (GITS), one tablet of which lowers blood pressure by as much as 24 hours, and it is enough to take it once a day.

In 2000, the results of the large INSIGHT study were published, which compared the efficacy of 24-hour-acting nifedipine with diuretic drugs for the treatment of hypertension. More than 6300 patients participated in this study. Half of them were taking nifedipine and the other half were taking diuretics (water pills). It turned out that nifedipine in the form of GITS (GITS) and diuretics approximately equally reduce blood pressure, overall and cardiovascular mortality. At the same time, among patients who were treated with nifedipine, new cases of diabetes mellitus, gout and atherosclerosis of the vessels of the legs were less common.

Nifedipine and its “relatives” (dihydropyridine calcium antagonists) play a particularly important role in the treatment of hypertension in patients with diabetes and metabolic syndrome (prediabetes). Because these drugs do not impair metabolism, that is, they do not affect blood sugar, cholesterol and triglycerides. Nifedipine 24-hour GITS is the drug of choice for blood pressure control in patients with diabetes, metabolic syndrome and high cardiovascular risk.

Nifedipine 24-hour action in the treatment of hypertension not only lowers blood pressure, but also largely protects the internal organs. The organoprotective effect of nifedipine is manifested in the following:

decrease in remodeling of the left ventricle of the heart; optimization of tissue blood supply; beneficial effect on kidney function; improvement of the functional state of the retina.

In the treatment of hypertension, nifedipine goes well with almost all groups of “pressure” drugs that are currently used:

diuretics (diuretics); beta blockers; ACE inhibitors; angiotensin-II receptor blockers.

If you prescribe nifedipine for pressure in combination with drugs from other groups, then in this way you can increase the effectiveness of treatment, reduce the dosage of tablets and reduce their undesirable side effects. Read more in the article “Treatment of hypertension with combination medications”.

Isolated systolic hypertension in the elderly

Among the elderly, at least 40-50% suffer from high blood pressure. In older patients, isolated systolic hypertension is especially common. High blood pressure reduces life expectancy, often causing a heart attack, stroke, or the development of chronic kidney failure. An effective drug for the treatment of hypertension in elderly patients should not only lower blood pressure, but also protect against target organ damage. Nifedipine (only in a long-acting formulation!) is one suitable drug in this case.

No more shortness of breath, headaches, pressure surges and other symptoms of HYPERTENSION! Our readers for the treatment of pressure are already using this method.

To learn more…

In 2008, specialists from the Medical Institute of Penza State University published an article on the results of a study on the effectiveness of the treatment of hypertension with long-acting nifedipine in 48 elderly patients. Of these 48 patients:

20 people suffered from isolated systolic hypertension; 28 had increased both “upper” and “lower” blood pressure.

The results of blood pressure reduction were assessed by measuring it with a tonometer at a doctor's appointment. In addition, each of the patients underwent 24-hour blood pressure monitoring at the beginning and after 24 weeks of treatment. Also, the authors of the study found out whether the “extended” nifedipine has the ability to protect target organs from damage. To do this, participants underwent echocardiography (heart), and they were tested for microalbuminuria - protein excretion in the urine - an important indicator for assessing kidney function.

The dynamics of the decrease in "upper" and "lower" blood pressure in elderly patients during treatment with nifedipine tablets of 24-hour action

Note to the table. All values ​​were obtained from the results of 24-hour blood pressure monitoring. The authors of the study found that as a result of the "white coat effect" at the doctor's office, systolic pressure is increased by an average of 13-15 mm Hg. Art.

Study participants noted that their blood pressure began to steadily decrease as early as the 2nd week of treatment, and this effect increased in the following weeks and months. The table shows that in patients with isolated systolic hypertension, nifedipine lowers the “upper” pressure significantly, and the “lower” pressure is much less. This suggests that nifedipine is the drug of choice for the treatment of isolated systolic hypertension in the elderly, because there is no excessive decrease in diastolic pressure.

Normally, in a healthy person, blood pressure decreases at night during sleep. The daily dynamics of blood pressure fluctuations can be tracked by the results of 24-hour monitoring using a special device. If it turns out that the patient’s blood pressure does not decrease at night, and even more so if it rises, then this is called an “abnormal blood pressure profile” and means that the risk of heart attack or stroke is significantly increased. In the study whose results we are discussing, 80% of patients with isolated systolic hypertension initially had an abnormal blood pressure profile. In the group of patients with systolic-diastolic hypertension, these were 65%. Treatment with 24-hour nifedipine appeared to improve the circadian blood pressure profile in many patients.

Microalbuminuria - the excretion of protein in the urine - at the beginning of the study was determined in 11 of 26 patients with systolic-diastolic hypertension and in all 20 (100%) patients with isolated systolic hypertension. Taking long-acting nifedipine tablets for 24 weeks led to the fact that in the first group the number of patients with microalbuminuria decreased from 11 to 9, and in the second - from 20 to 8. Thus, it was confirmed that nifedipine protects the kidneys.

Left ventricular hypertrophy is a way for the heart to adapt to the increased workload that occurs due to arterial hypertension. If studies show that the patient has a change in the shape (remodeling) of the heart, then this significantly worsens his prognosis. Because the risk of a heart attack increases. In a study on the treatment of hypertension in elderly patients, the effect of nifedipine therapy on the degree of left ventricular hypertrophy was tested. According to the results of echocardiography, it was found that taking 24-hour nifedipine reduced the thickness of the walls of the heart, improved systolic and diastolic function of the left ventricle, and reduced total peripheral vascular resistance. Thus, hypertrophy of the left ventricle of the heart regressed in many patients.

Since nifedipine had a positive effect on the function of the heart and kidneys, it can be argued that it not only lowers blood pressure, but also protects target organs from damage in elderly patients. In the group of patients with isolated systolic hypertension, all 20 people (100%) completed the study. In the group of patients in whom both “upper” and “lower” blood pressure were elevated, 2 people dropped out due to side effects of nifedipine. They had flushes of blood to the skin of the face and swelling.

See also articles:

Isolated systolic hypertension in the elderly - in detail; Drug treatment of hypertension in the elderly; What medications for hypertension are prescribed for elderly patients.

Cardiac ischemia

Nifedipine is widely used to treat coronary heart disease. It clearly reduces pain in the heart, reduces the frequency of angina attacks in patients and reduces the need for nitroglycerin. All of this has been proven in clinical studies since the early 1980s. Against the background of taking nifedipine in a dosage form of prolonged action, exercise tolerance increases. This drug is not inferior to beta-blockers and nitrates in terms of effectiveness for heart problems.

In accordance with international recommendations, beta-blockers are the main group of drugs for prescription in coronary heart disease. In the practice of a doctor, the question often arises: which drug is better to add to them? Which additional drug will provide a more pronounced antianginal effect - nitrates or nifedipine?

In the recommendations of the American Heart Association for the treatment of stable angina pectoris, the effectiveness of nitrates and dihydropyridine calcium antagonists was recognized as equal. However, it is advised to give preference to extended-life nifedipine because it remains effective for 24 hours. Another advantage of dihydropyridine calcium antagonists compared to nitrates is that patients are much less likely to develop addiction to them.

In the practical work of a doctor, dihydropyridine calcium antagonists, including nifedipine, become the drugs of choice if the appointment of beta-blockers is contraindicated. These situations include:

sick sinus syndrome; atrioventricular block; bronchial asthma.

Also, dihydropyridines can sometimes be prescribed in cases where verapamil and diltiazem, non-dihydropyridine calcium antagonists, are contraindicated. This occurs if the patient has sick sinus syndrome or severe atrioventricular block.

In 2004, the results of the large-scale ACTION study were published, in which 7665 patients with coronary heart disease or myocardial infarction took part. The aim of this study was to investigate the effect of adding nifedipine 24-hour GITS (see What Nifedipine Formulations Are Available) to the conventional regimen. Patients were treated prior to study entry and continued to be treated with beta-blockers, statins, ACE inhibitors, and aspirin. They were divided into two groups. Those who entered the first group were added nifedipine to the treatment, and patients from the second group received a placebo for control.

The doctors followed up all the study participants for 5 years. It turned out that nifedipine in the form of GITS did not improve or worsen overall and cardiovascular mortality, as well as the incidence of new cases of myocardial infarction. But he reduced the number of new cases of heart failure by 29%, strokes by 22%, and the need for coronary artery bypass surgery by 14%. Among patients in whom coronary heart disease was combined with hypertension, the results were even better, by about 1.5 times. There were no more side effects from taking the “extended” nifedipine GITS than from placebo. The authors of the study explained the effectiveness of nifedipine by the fact that it additionally lowered blood pressure in patients, and also inhibited the development of atherosclerosis.

Kidney Protection in Hypertension and Diabetes

If the patient has kidney damage due to diabetes or other reasons, then the target blood pressure level for him will be 130/80 mm Hg. Art., and not 140/90, as for people with healthy kidneys. If proteinuria (protein excretion in the urine) is more than 1 g per day, then the target blood pressure level is even lower - 125/75 mm Hg. Art. To protect the kidneys in hypertension, you need to ensure strict control of blood pressure, stop smoking and try to normalize blood cholesterol levels.

Obviously, regular intake of blood pressure pills can significantly slow down the development of kidney failure. With intensive treatment, the likelihood increases that the patient's own kidneys will last the rest of his life, and he will not have to experience the “charms” of dialysis or a kidney transplant. Studies have shown that all major classes of hypertension drugs reduce kidney damage. But which drugs do it better than others?

Calcium antagonists relax and dilate the blood vessels that feed the kidneys. Under the action of nifedipine, renal blood flow, levels of glomerular filtration and filtration fraction increase. Calcium antagonists slow down the development of nephrosclerosis. Long-acting (not short-acting) nifedipine reduces microalbuminuria. This medicine preserves kidney function in patients with diabetes mellitus and diabetic nephropathy. Nifedipine protects the kidneys both directly and by lowering blood pressure.

Nifedipine and other calcium antagonists are especially often used to inhibit the development of renal failure if the patient has hypertension and diabetes. Because in such cases it is contraindicated to prescribe diuretic drugs or beta-blockers. But which drugs protect the kidneys better - calcium antagonists, ACE inhibitors or angiotensin-II receptor blockers (sartans)? This issue has not yet been fully elucidated and requires further research.

In 2000, the results of a large study were published, which showed that nifedipine prevented kidney failure more effectively than diuretics (diuretics). We also mention that this medicine to some extent increases the sensitivity of tissues to insulin. Thus, the course of hypertension in diabetes improves.

Slowing the progression of atherosclerosis

Back in the 1990s, studies using short-acting nifedipine showed that the drug had a beneficial effect on metabolism and, to some extent, slowed down the development of atherosclerosis. An indicator that characterizes the risk of cardiovascular complications is the thickness of the intima-media complex (IMT) of the carotid arteries. It is measured using ultrasound. The greater this thickness, the higher the patient's risk of heart attack or stroke. Studies have reliably shown that taking nifedipine slows down the growth of IMT. Moreover, this effect of the drug does not depend on its action to lower blood pressure.

Another important risk factor is calcium deposits in atherosclerotic plaques on the walls of arteries. Calcium makes them hard and looks like limescale on water pipes. The process of calcium accumulation in atherosclerotic plaques is called calcification. It turned out that nifedipine, although slightly, slows down the calcification of the coronary (heart-feeding) arteries.

It is now believed that nifedipine slows down the development of atherosclerosis better than other calcium antagonists. At the same time, one should not hope to completely slow down atherosclerosis with the help of nifedipine alone. We recommend testing for atherosclerosis risk factors, which are listed in the article “Causes of hypertension and how to eliminate them. Tests for hypertension. It also indicates what measures effectively help protect blood vessels from atherosclerosis.

Nifedipine during pregnancy

With long-term therapy with nifedipine, started in early pregnancy, cases of intrauterine fetal death and skeletal anomalies in newborns are described. It is believed that nifedipine and other dihydropyridine calcium antagonists (with the exception of amlodipine) are not safe in the first trimester of pregnancy, so they are not recommended for women of childbearing age. At the same time, some studies have shown that nifedipine is able to effectively control arterial hypertension in women in late pregnancy (not earlier than 18-21 weeks), without adversely affecting the development of the fetus.

Nifedipine, administered sublingually and orally, has proven to be particularly useful in the treatment of hypertensive crises in pregnant women. There are separate reports in the literature on the safety of the use of dihydropyridine calcium antagonists in late pregnancy. However, there are few of them, and therefore, for the time being, nifedipine is not recommended in pharmacological reference books for use during pregnancy. Doctors prescribe it only in severe cases, when they believe that the benefits of taking the pills will be greater than the risks.

Do not take nifedipine without permission during pregnancy! Consult a doctor!

In 2008, specialists from the Medical Institute of the State University of the Ukrainian city of Sumy published the results of their small study on the efficacy and safety of nifedipine in the treatment of chronic hypertension, preeclampsia and gestational hypertension during pregnancy. Under their supervision there were 50 pregnant women with hypertension, who were divided into three groups:

group 1 included 20 pregnant women with gestational hypertension (which began during pregnancy); group 2 - 20 pregnant women with preeclampsia; in the 3rd group - 10 pregnant women with chronic hypertension, which they had before pregnancy.

Comprehensive examination of pregnant women was repeated regularly to assess changes. It included a general clinical examination, an assessment of the state of the fetus according to functional methods (determination of the biophysical profile of the fetus), a Doppler study. Determination of the biophysical profile of the fetus was performed by transabdominal scanning using an ultrasonic portable scanner "Aloka SSD - 1800 (Toshiba, Japan) with a sensor from 3.5 to 10 MHz. The biophysical profile of the fetus was assessed based on the assessment of fetometry data, antenatal cardiotocography, the results of the study of fetal tone, respiratory and motor activity, ultrasound placentometry, and determination of the volume of amniotic fluid. The condition of newborns was assessed on the basis of a general clinical examination, examination by a geneticist, and ultrasound examination.

Nifedipine has been used in gestational hypertension and preeclampsia, as well as in chronic hypertension in pregnancy as an effective fast-acting agent and for long-term therapy at 12-38 weeks of gestation. The indication for prescribing short-acting nifedipine tablets was an increase in blood pressure to a level of 150100 mm Hg. and higher. The drug was administered orally in single doses of 5 and 10 mg and sublingually 10 and 20 mg. Daily doses ranged from 30 to 120 mg. The dose of the drug for each patient was selected individually.

Studies have noted a rapid and significant decrease in blood pressure (systolic by the 30th minute, diastolic by the 20th minute when taken orally), which persisted for 2-4 hours. An even faster action was observed when the drug was applied under the tongue. The severity of the effect on lowering blood pressure was almost the same in pregnant women who did not receive any prior treatment, and in those patients who received methyldopa therapy before the appointment of nifedipine. Carrying out daily monitoring of blood pressure, revealed that the drug has a powerful effect. At the same time, in pregnant women with chronic hypertension, after dose selection, the effect remained the same over a 24-hour period. Their blood pressure did not exceed 120/90 mmHg.

A similar picture was observed in the group of women with gestational hypertension. In women with preeclamisia, blood pressure was less stable during the day, the effect of taking nifedipine was especially pronounced in the evening and at night. In some cases, nifedipine therapy was supplemented by the introduction of clonidine (clophelin). Five pregnant women were admitted to the hospital during a hypertensive crisis. In order to stop the latter, nifedipine 10 mg under the tongue was used. A positive result was achieved by taking the drug twice in 30 minutes.

Side effects of nifedipine during pregnancy

In pregnant women who received nifedipine, side effects were noted from:

fetal heart rate (unstable heart rate - in 14.0%, tachycardia - in 8.0%); respiratory movements of the fetus (an increase in the number of episodes of respiratory movements - in 14.0%, a violation of the form of the respiratory movements of the fetus - movements of the gasps type - in 10.0%); motor activity of the fetus (increased motor activity - in 6.0%); fetal tone (decrease - in 6.0%).

Retardation of intrauterine development of the fetus was observed quite often - in 60.0%, polyhydramnios - in 20.0% of pregnant women, oligohydramnios - in another 20.0%.

When studying the structure of the placenta in 10.0% of pregnant women, there was a decrease in the intervillous space. In pregnant women who received pressure pills, placental hypertrophy (12.0%) was observed less frequently than hypoplastic changes (30.0%). During the study, a lag in its maturation of 18.0% was revealed. Destructive changes in the placenta were observed rarely - 2.0%. Placental abruption was diagnosed in 2 (4.0%) pregnant women.

In 7 women (14.0%) with signs of intrauterine infection of the fetus, changes in the structure of the placenta were accompanied by a violation of the nature of the fetal heartbeat (tachycardia, unstable heart rate), in 4 (8.0%) women - a change in the motor activity of the fetus, in 9 (18 .0%) - a violation of respiratory activity and in 3 (6.0%) - a decrease in fetal tone. When assessing the biophysical profile of the fetus, it was noted that in pregnant women treated with nifedipine, it was 4.6±0.3 points. Signs of a compensated form of fetoplacental insufficiency (4 points) were determined in 80.0% of pregnant women of the main group, subcompensated form (3 points) - in 20.0%.

All newborns had an Apgar score of 8-10 at birth, while the maximum score was 10. Examination of newborns by a geneticist and an ultrasound study showed that the use of nifedipine by women during pregnancy did not lead to the appearance of fetal malformations. Thus, nifedipine, according to clinical studies, is not only an effective, but also a fairly safe drug for the treatment of pregnant women.

Read also articles:

Hypertension and pregnancy Drug treatment of hypertension in pregnant women Pre-eclampsia is a dangerous complication of pregnancy

How to take nifedipine

For long-term treatment of hypertension and coronary heart disease, it is recommended to take only “extended” nifedipine, which lasts 12 or 24 hours. Short-acting nifedipine is only suitable for emergency care when you need to quickly stop a hypertensive crisis. If you take rapid-acting nifedipine for a long time, it will increase your risk of heart attack and stroke.

The dosage of the drug can only be selected by an experienced doctor, strictly individually. Attempts to self-medicate with nifedipine, based on the dosages indicated in the instructions for the tablets, lead to disastrous results. Therefore, do not self-medicate. Find a good doctor you can trust and consult with him. Note that magnesium tablets are a healthy alternative to nifedipine to treat hypertension and coronary heart disease without side effects.

How much better is the prognosis for the patient

Modern therapy for cardiovascular diseases affects the symptoms that cause discomfort to the patient. Medicines normalize high blood pressure and reduce pain in the heart area. But the main task of doctors is to improve the prognosis, that is, to prevent severe complications. First of all, it is a myocardial infarction and a cerebral stroke.

The question of how calcium antagonists, including nifedipine, affect the prognosis has been discussed from the very beginning of the use of these drugs in clinical practice. In a study in 1986, it was shown that taking short-acting nifedipine 10 mg 6 times a day by patients with unstable angina did not reduce, but even increased the risk of heart attack. A 1988 study followed. Its authors found that if nifedipine is prescribed in the acute period of myocardial infarction or immediately after a heart attack, then this definitely does not improve the prognosis, and possibly even worsens it. This study also used short-acting nifedipine.

After analyzing the results of these studies, the doctors came to the conclusion that short-acting nifedipine is not a "strategic" drug. It is suitable only for the rapid relief of hypertensive crises, but not for regular use in order to systematically treat and prevent acute cardiovascular “events”. The situation has changed with the advent of nifedipine retard tablets, which act for 12 hours. They were followed by the release of nifedipine controlled-release preparations on the market, which remain effective for 24 hours. The most popular of them are OSMO-Adalat and Corinfar UNO.

In 2000, the results of a study in which more than 6,000 hypertensive patients participated were published to compare the effectiveness of nifedipine and diuretic drugs. This study used the most advanced 24 hour nifedipine in the form of GITS (Gastrointestinal Therapeutic System). It turned out that 3-year therapy with “extended” nifedipine reduced overall and cardiovascular mortality no worse than treatment with diuretic drugs. At the same time, patients in the nifedipine group were less likely to develop diabetes than those who took diuretics.

In 2004, the results of a large and long-term study of the effect of adding nifedipine GITS to the treatment of stable coronary heart disease were presented. More than 7600 patients participated in this study. They were treated with drugs from the class of beta-blockers, aspirin, statins and nitrates before the start of the study. They were divided into groups. Patients of the first group were added nifedipine-GITS 60 mg per day to the previous treatment, and placebo was added to patients in the control group. After 6 years of follow-up, nifedipine supplementation appeared to have little or no effect on overall mortality, myocardial infarction, or stroke. But in patients who received additional medicine, there was less need for operations for blockage of blood vessels that feed the heart. This proves that nifedipine to some extent inhibits the development of atherosclerosis.

Nifedipine: implications for clinicians and patients

Long-acting nifedipine (12-24 hours) has been used in domestic practice since the early 2000s. During this time, the drug has confirmed its effectiveness and safety for the treatment of patients with hypertension and chronic coronary heart disease. Only long-acting nifedipine has been shown to prevent heart attacks and strokes. Most likely, drugs that last 24 hours (OSMO-Adalat, Corinfar UNO and others) are a better choice than nifedipine tablets that last 12 hours.

Unfortunately, the vast majority of doctors don't bother reading medical journals. Therefore, they continue to favor short-acting nifedipine. Do not use rapid-acting nifedipine to treat hypertension and coronary heart disease! It does not improve overall and cardiovascular mortality rates, and most likely even worsens them. Short-acting nifedipine is only suitable for emergency relief of hypertensive crises.

Long-acting nifedipine can be given to effectively maintain stable blood pressure control and to some extent slow the development of atherosclerosis. This drug proved to be safe enough for the complex treatment of stable angina pectoris. To date, studies have convincingly proven that it is advisable to widely use "extended" nifedipine. There are no scientifically sound data that would limit the use of this drug in patients with hypertension, kidney damage and coronary heart disease, in the absence of contraindications.

In 2008, the book Reverse Heart Disease Now by American cardiologists Stephen T. Sinatra and James C. Roberts was published in English. If you read English, it will be very useful to study this wonderful book. It is written in an accessible language, intended for doctors and patients. It, among other things, says that instead of drugs from the group of calcium antagonists, it is recommended to use magnesium tablets. Like, magnesium deficiency in the body is one of the main causes of hypertension and cardiovascular disease. The action of drugs from the group of calcium antagonists only “masks” this deficiency.

Nifedipine, even its modern extended-release dosage form, often causes negative side effects. You may have already had the "pleasure" of experiencing them for yourself. If the theory of American cardiologists is correct, then it would be much more effective to take magnesium tablets instead of nifedipine, which are sold in pharmacies. On our website, thousands of people have already learned that magnesium in combination with vitamin B6 is good for hypertension and cardiovascular diseases. We've received dozens of rave reviews from readers that confirm this.

Therefore, if nifedipine or other calcium antagonists are helping you, it makes sense to try magnesium supplements instead. The benefits to your health and longevity can be enormous. And if you fail, you have nothing to lose. Because you can always go back to drugs. For the first 1-2 weeks, take magnesium along with "chemical" pills. If everything is fine, then you can try to reduce the dosage of the medicine, slowly and carefully, monitoring your well-being and blood pressure.

Medication Definition

Nifedipine

is a prominent representative of antihypertensive drugs (

lowering blood pressure

) and antianginal (

reducing chest pain

) actions. This drug belongs to the group of calcium channel blockers. In connection with this mechanism of action, nifedipine has a pronounced relaxing effect on the smooth muscles of all organs and blood vessels. A particularly pronounced vasodilating effect is observed in relation to arterial vessels, rather than venous ones.

This drug has many benefits. One of them is the possibility of using it both in emergency conditions and in chronic ones. With an attack of retrosternal pain, a tablet of the drug is placed under the tongue and chewed, after which the pain disappears after 5 to 15 minutes. Long-term use of the drug is encouraged with stable

angina pectoris

In this case, mainly forms of the drug with prolonged action are used.

This drug is convenient to dose, which is extremely important in view of the fact that for each patient the regimen is compiled individually, taking into account the degree of compensation of his disease, as well as the individual characteristics of the organism. In addition, nifedipine is successfully combined with most drugs for many diseases that often accompany the main one. However, it is important to familiarize yourself with the features of parallel drug administration, since some of them can affect the rate of neutralization and elimination of each other.

It should also be noted that nifedipine has long been used in obstetrics as a tocolytic, that is, a drug that reduces the tone of the myometrium - the muscle layer.

Due to this action, this drug was used for the purpose of carrying

pregnancy

under acute threat

miscarriage

Currently, there are more advanced drugs used for this purpose, with targeted action and less pronounced side effects, but in some cases, nifedipine is preferred due to its effects on the cardiovascular system.

The negative aspects of this remedy come from the positive aspects. In other words, nifedipine is a drug with pronounced physiological effects. If used ineptly, it is likely to do more harm than good, so it should never be used without consulting a doctor.

For patients under 18 years of age, this drug can be prescribed only in exceptional cases, since there is no confirmation of its safety for this category of patients today. In other words, it is not known whether nifedipine will act on the child's body in the same way as an adult or in some other way.

The same dilemma arises for pregnant women. According to some reports, the drug is relatively safe only in the last trimester of pregnancy. In the first two, its use can potentially cause a negative effect on the fetus. However, the degree of such a possibility is little studied, since a negative effect was observed only on animal embryos, and such experiments have not been carried out on humans and are unlikely to ever be carried out.

Due to the fact that the drug penetrates the secret

mammary glands

Types of medication, commercial names of analogues, release forms

Nifedipine is produced in the form of three dosage forms:
dragee; tablets; solution for intravenous drip.

Dragees are small balls with a preparation that contain 10 mg of the active substance, as well as various stabilizers, dyes, etc. Dragees are often sweet in taste, therefore they are used mainly sublingually (

placed under the tongue and absorbed

), unlike simple tablets that do not always have a pleasant taste. However, you can dragee and swallow, then they act like simple tablets. The area of ​​application of the dragee is urgent conditions at the pre-hospital and hospital stages. Less often they are used for permanent treatment due to the need for multiple doses during the day.

Nifedipine tablets come in two types - short-acting and extended-release. Short-acting tablets of 10 and 20 mg are mainly used when it is necessary to reduce high blood pressure or get rid of retrosternal pain in rare attacks in relatively healthy patients. In such cases, the use of this drug is episodic. Long-acting tablets are used to compensate (

keeping under control

) arterial hypertension and

ischemic heart disease

This type of medication is more convenient, since the need to take it is reduced from 3 total to 1 time per day. Moreover, such tablets are available in a wide variety of doses from 20 to 60 mg, which allows you to most accurately adjust the treatment of each patient.

The solution for intravenous drip is available in dark glass bottles, 50 ml. The concentration of the solution is 0.1 mg/ml or 0.01%. The scope of its application is exclusively the cardiology department or the intensive care unit, due to the high activity of the drug when administered intravenously.

Nifedipine exists on the pharmaceutical market under the following commercial names:

Corinfar; Cordaflex; Nifesan; Sanfidipin; Nifelat; Nifecard; Cordipin; Nifedicor; Nifedex; Nifehexal; Nifadil; Nicardia; Adalat and others

Manufacturers of nifedipine

The mechanism of the therapeutic action of the drug

Nifedipine is completely absorbed from the mucous membranes of the digestive tract. Moreover, when the tablet is placed under the tongue, the speed of the onset of the effect is shortened, however, as is the duration of the effect. After penetration into the blood, approximately 90% of the drug binds to plasma proteins, which ensures its long-term presence in the body. The same part of the substance that did not bind to proteins is directly responsible for the development of the effect of the drug. As the freely circulating substance is consumed or inactivated by the liver cells, some of the bound substance is released from the blood proteins and converted to the free active form. Thus, the therapeutic concentration of nifedipine in the blood is maintained for several hours.

In view of the foregoing, it can be concluded that the bioavailability of the drug (

the ratio of the active substance that has reached its goal to the entire administered single dose

) is equal to 40 - 60% on average. The main losses of the drug occur during the first passage through the liver, while most of it has not had time to bind to plasma proteins.

The point of application of this drug is the plasma membrane of muscle cells. Nifedipine blocks the channels for the entry of calcium ions into the cell, as a result of which calcium does not penetrate into it. The chemical reactions responsible for the development of muscle contraction slow down. The most active drug affects cardiomyocytes (

muscle cells of the heart

) and smooth muscle of arterial blood vessels. Nifedipine has no effect on the veins, since their muscle layer is poorly expressed. In addition, in medium and large doses, the drug has a strong antispasmodic effect on the smooth muscles of the internal organs. In this regard, nifedipine has been used for a long time in obstetrics and nephrology. In obstetrics - with the threat of miscarriage, due to increased uterine tone, and in nephrology - for relief

renal colic

To date, there are more advanced drugs used for this purpose, but, nevertheless, in special cases, nifedipine may remain the drug of choice.

The main effect of nifedipine is aimed at:

heart; peripheral vessels. Nifedipine has the following effects on the heart: negative inotropic (reducing the force of contraction of the heart); negative chronotropic (reducing the heart rate); negative dromotropic (reducing the speed of the nerve impulse through the conduction system of the heart). The most pronounced is the inotropic effect. Chronotropic and dromotropic effects are less pronounced. As a result, a decrease in the intensity of the work of the heart leads to a decrease in the demand of the myocardium (the muscular layer of the heart) for oxygen. In this regard, pain in angina caused by hypoxia (insufficient supply of oxygen to the tissues of the organ) of the heart decreases. The expansion of the coronary vessels that feed directly to the heart leads to an increase in the supply of oxygen-rich blood. Vascular collaterals that were previously unused open, which leads to improved nutrition of ischemic (insufficiently supplied with blood and, accordingly, oxygen) areas of the myocardium.

However, it should be remembered that when using an excessive dose of the drug, especially in subcompensated and decompensated patients, a reflex reaction often develops.

tachycardia increased heart rate

) to increase the ejection fraction (

indicator, conditionally designating the efficiency of the heart

On blood vessels, nifedipine has a single dilating effect, but this leads to many positive effects.

The vasodilating effects of nifedipine are as follows:

lowering blood pressure; reduction of afterload on the heart, increasing the efficiency of its work; elimination of hypertension in the pulmonary circulation - a decrease in shortness of breath due to an increase in the diameter of the bronchi; improvement of cerebral circulation; improving the excretory function of the kidneys by expanding the renal artery and increasing the excretion of sodium and water ions. Since the drug practically does not penetrate the blood-brain barrier, you can not be afraid of side effects on the central nervous system (central nervous system). However, if the patient had a serious traumatic brain injury in the past or had symptoms of any mental illness, the likelihood of drug effects on the brain increases, and at the same time the risk of side effects from the central nervous system.

The drug penetrates the placenta, but in small quantities. However, based on this alone, it cannot be concluded that this medicine is harmless to pregnant women. Unfortunately, no studies have been conducted to investigate this issue. Therefore, pregnant women are advised to take the drug, only after consulting with a doctor first. According to clinical observations, its use in the third trimester of pregnancy at standard doses is relatively safe.

Among other things, the active substance passes into the milk of nursing mothers. Its concentration in milk is almost equal to that in blood plasma. Therefore, if it is necessary to use nifedipine, the child must be weaned and fed with artificial nutrient mixtures throughout the treatment. Otherwise, doses that are normal for the mother may be excessive for the child and cause an overdose in his small body with all the complications that follow from this.

Removal of the main part of the drug (

) is excreted by the kidneys as inactive metabolites. small part (

) is also excreted as metabolites along with the stool. The remaining few percent are removed from the body through sweat, breath, saliva, etc.

kidney failure

Contrary to expectations, it does not lead to the accumulation of the drug and its overdose, and also does not worsen its excretion from the body. However

liver failure

can significantly increase the half-life of the active substance. In this regard, patients with severe

cirrhosis

the liver should be careful about the selection of the required dose of the drug or look for other drugs to lower blood pressure and eliminate retrosternal pain.

Indications for use

The main area of ​​application of nifedipine is the maintenance of blood pressure within normal limits and the elimination of retrosternal cardiac pain in cardiac patients. The main contingent of patients are people older than 40 years. Patients under 18 years of age are not prescribed the drug, due to the lack of reliable data on its safety in this group of people.

The use of nifedipine

How to apply the medication?

Nifedipine has a long history of clinical use and has proven to be an effective first-line drug for acute episodes and maintenance treatment of hypertension and coronary heart disease. It is prescribed only to patients who have reached the age of 18 years. The safety of its use in children has not been proven.

The method of administration of nifedipine should meet the goals of treatment and correspond to the patient's condition.

This drug is introduced into the body in three ways:

inside; under the tongue; intravenous drip or infusion pump.

Oral administration of nifedipine

The advantages of this drug administration are simplicity and a relatively slow onset of effect (20-30 minutes when taking simple tablets and up to 60 minutes when taking prolonged-release tablets). However, part of the drug is lost due to the effect of the first passage through the liver during absorption from the digestive tract.

The use of this drug by mouth is indicated for stable exertional angina, when the effects of the drug are more or less predictable. Also, the drug is prescribed both for primary essential arterial hypertension, and for secondary - renal, hormonal, etc. In these cases, the drug is taken without chewing 10-20 mg 2-4 times a day in the form of simple tablets or 20-40 mg 1 - 2 times a day in the form of tablets of prolonged action.

Sublingual administration of nifedipine

The advantages of this method of drug administration are the simplicity and speed of the onset of the effect (

5 to 10 minutes

). This effect is ensured by the direct entry of the substance into the blood through the mucous membrane of the oral cavity. Thus, the drug is not immediately detoxified in the liver, but first has time to have a therapeutic effect. In this case, simple tablets are recommended to be chewed and kept under the tongue, and prolonged-release capsules should be opened or pierced. An important condition for this method of prescribing the drug is the use of single minimal doses in order to avoid an excessive drop in blood pressure and the development of shock and other undesirable reactions.

This method of taking the drug is practiced in acute conditions, such as

hypertensive crisis

An attack of angina pectoris or

bronchial asthma only in combination with hormonal drugs and classic bronchodilators

). In such conditions, the use of nifedipine is one-time. The optimal dose is 10 - 20 mg.

Prescribing intravenous nifedipine

Nifedipine is prescribed intravenously only in a hospital setting and, preferably, an intensive care unit. This limitation exists for several reasons. One of the reasons is the exact dosage and rate of intravenous administration of the active substance, which can be ensured by accurate calculation of drops per minute with drip administration or using an infusion pump. Another reason is that the drug is administered intravenously only to patients who are in serious and extremely serious condition and cannot take the medicine otherwise than intravenously. In addition, with the development of undesirable effects, the frequency of which increases in this category of patients, the drug can be immediately canceled and its antagonist administered to normalize the general condition of the patient.

Preparation of a solution for infusion is not required, since it is available in a standard dilution in dark glass bottles of 50 ml, each containing 5 mg of the active substance. Before administration, it is mandatory to conduct a skin allergy test to exclude an allergic reaction of the body to this substance. Only under the condition that the test is negative can the drug be administered.

Nifedipine is administered intravenously very slowly. One 50 ml vial is administered over 4 to 8 hours. For a stable effect, this drug must be administered at least 3 times a day. In some conditions, the appointment is allowed up to 6 times a day. The maximum daily dose is therefore 150-300 ml or 15-30 mg.

Possible side effects

Due to the fact that nifedipine is a drug that directly affects the functioning of the heart and hemodynamics, the most dangerous side effects from its use are associated with the cardiovascular system. There are also some side effects from the nervous, respiratory, digestive systems, musculoskeletal system, etc., which can significantly worsen the patient's condition.

There are side effects of nifedipine from:

of cardio-vascular system; central nervous system; gastrointestinal tract; respiratory system; musculoskeletal system; allergic reactions, etc. Cardiovascular disorders:

reflex tachycardia; strong heartbeat; redness of the skin of the face; excessive decrease in blood pressure; chest pain, etc. Central nervous system disorders:

headache; dizziness; paresthesia (feeling of "goosebumps"), etc. Gastrointestinal disorders:

constipation; diarrhea; stomach ache; nausea, etc. Respiratory system disorders:

bronchospasm; shortness of breath, etc. Musculoskeletal disorders:

muscle pain; hand shaking, etc. Allergic reactions: hives; contact dermatitis; angioedema (Quincke's edema); anaphylactic shock, etc.

Interactions with other drugs

When interacting with beta-blockers, a synergistic clinical effect is observed. In other words, there is a risk of a sharp drop in blood pressure with the development of compensatory tachycardia and aggravation of heart failure. The interaction of nifedipine with magnesium salts (for example, magnesia sulfate) is also dangerous due to the risk of a sharp drop in blood pressure. In addition, there is a high probability of developing a neuromuscular block, which is expressed by severe weakness, inaccurate movements, shortness of breath, difficulty swallowing, etc. In connection with the foregoing, pregnant women with preeclampsia and eclampsia are primarily recommended to use magnesium sulfate. With a weak effect, the use of nifedipine is contraindicated. Instead, loop diuretics (diuretics such as furosemide, torasemide, etc.), ACE inhibitors (angiotensin converting enzyme, such as captopril, enalaprilat) and other methods are used, but for a short time. Childbirth is the only way to stop the progression of preeclampsia and eclampsia. Combined use with digoxin leads to a delayed elimination of the latter, and, accordingly, to the risk of developing bradycardia (heart rate less than 60 / min) and a paradoxical arrhythmogenic (causing arrhythmias) effect. With the combined use of nifedipine and tacrolimus (an immunosuppressant), the neutralization of the latter in the liver slows down, which leads to its accumulation. In this regard, the dose of tacrolimus must be reduced by 26 - 38% to avoid side effects.

Interaction with phenytoin and

carbamazepine

is fraught with a decrease in the effectiveness of nifedipine by 70%. In this regard, it is recommended to change nifedipine to an alternative antihypertensive drug from a different pharmacological group.

The use of nifedipine with rifampicin is contraindicated, since the latter increases the activity of liver enzymes, thereby converting almost all of nifedipine during the first passage through the liver.

Approximate cost of medication

The cost of the medication may vary slightly in different regions of the Russian Federation. The difference in price is explained by different mechanisms for the production of the drug, raw materials, transportation costs, customs fees, pharmacy mark-ups, etc.

The cost of nifedipine in various regions of the Russian Federation

Can nifedipine be taken during pregnancy?

To date, nifedipine is used only in the last trimester of pregnancy for strict indications.

This restriction has a good reason. In the first and second trimester of pregnancy in the body of the fetus, the laying of future vital organs and systems takes place. Any impact, be it a drug, household chemicals or just

can affect the pace and correctness of the processes of division and differentiation (

acquisition of features characteristic of the cells of a particular tissue

) fetal cells. In the future, such a mistake can lead to more or less severe anomalies of physical or mental development. For this reason, it is recommended to refrain from all systemic drugs in the first 6 months of pregnancy and use them only when absolutely necessary, when the expected benefit outweighs the potential harm. Topical drugs do not create high concentrations of the active substance in the blood, so they are practically harmless to the fetus.

In the last trimester of pregnancy, the risks of harming the fetus are significantly reduced if the dose is correctly selected for a particular pregnant woman. All vital organs already exist at the moment and are gradually increasing in size.

The annotation to nifedipine states that according to the teratogenicity of the effect (

ability to cause congenital malformations

) it belongs to FDA group C drugs (

Food and Drug Administration - US Department of Health Food and Drug Administration

). This means that studies have been conducted to study the harm of this drug to the fetus of animals, which confirmed that some harm is still present. In humans, such experiments have not been carried out. Medicines that fall into this category may be prescribed to pregnant women, but only if the expected benefit outweighs the potential harm.

Despite the fact that nifedipine crosses the placenta in very low concentrations and practically cannot harm the fetus, no one undertakes to argue the opposite until special studies are carried out on pregnant women. However, due to the fact that such studies are inhumane, the probability of their implementation approaches zero. Thus, the data that science has to date regarding the safety of nifedipine for pregnant women are unlikely to be replenished in the near future, so you will have to be content with what is.

It is important for pregnant women to remember that nifedipine is not such a harmless drug, such as, for example,

vitamins

or nutritional supplements. It has a strong effect on many body systems, so it requires a clear dosage. When accidentally taking a high dose, first of all, blood pressure is greatly reduced. For any person, this threatens to worsen their well-being, up to loss of consciousness due to oxygen starvation of the brain. For pregnant women, the risks are doubled, because at low pressure not only the mother’s body suffers, but also the fetus, which receives less oxygen and nutrients due to poor blood supply to the placenta.

When deciding whether or not a pregnant woman should take nifedipine, one should decide on the purpose for which this drug was prescribed. If the goal is to reduce blood pressure in hypertension, then it would be more correct to choose a drug from another pharmacological group that does not affect the fetus. Such drugs exist, and their choice is quite large. Definitely, the search will not be done by the woman herself, but by her attending physician. In this case, nifedipine can be successfully replaced with diuretics (

furosemide, torasemide, indapamide, spironolactone, etc.

), magnesium sulfate, antispasmodics (

drotaverine, mebeverine, papaverine, etc.

sedatives, valerian tablets, etc.

If a pregnant woman takes nifedipine to reduce the frequency and intensity of retrosternal pain (

such conditions may well be in young mothers with congenital or acquired heart defects

), then nifedipine can certainly be replaced with nitro drugs such as isosorbide dinitrate (

kardiket

), isosorbide mononitrate (

allowed only in the second and third trimester

With the threat of preterm labor, nifedipine can be used, but only in the last trimester of pregnancy. It is preferable that this drug be used in low doses and in complex therapy with other drugs that reduce uterine tone. There are also plenty of such resources. The most prominent representatives are antispasmodics (

baralgin, papaverine, drotaverine, mebeverine, etc.

), agents that reduce uterine activity (

magnesium sulfate, magnesium B-6, etc.

), beta adrenomimetics (

partusisten, terbutaline, etc.

Summing up the above, it should be noted that nifedipine is not an indispensable drug for pregnant women. If necessary, its effects may well be replaced by one or a combination of drugs, depending on which of its effects is needed in the treatment.

Can Nifedipine be taken while breastfeeding?

The use of nifedipine in

breastfeeding

highly undesirable due to the fact that the drug in unchanged form is able to penetrate into breast milk and have an undesirable effect on the child.

When it enters the human body, this drug is evenly distributed in all tissues and organs, with the exception of the brain, since it is not able to overcome the blood-brain barrier. However, in people who have suffered a serious traumatic brain injury in the past or suffer from certain mental illnesses, this barrier may be weakened. This promotes the penetration of more drugs into the brain, which often causes side effects from the central nervous system.

So, distributing throughout the body, nifedipine enters the mammary glands and directly into their secret - breast milk. Given that bioavailability (

the proportion of the substance that has an effect on peripheral tissues in relation to the total administered dose

) of this medicine is equal to 40 - 60% in the body of a child through milk can enter with one average feeding (

) from 1:40 to 1:80 of the adult dose. Considering that the weight of a child is less than the weight of an adult by an average of 10-15 times, such a dose may seem relatively small for the manifestation of the clinical effect of nifedipine in a child. However, it is not.

In the womb, the child prepares for the transition to the outside world, and its internal organs develop just enough to endure this transition. Their further growth and development occurs after birth for at least 25-28 years. However, the most significant changes are observed in the first year of life. During this period, the tissues of the baby are extremely sensitive to any kind of biological and chemical signals. Therefore, the dose of nifedipine, which by all accounts, when taken with milk, should be too small for a child, is actually too high.

Overdose leads to two types of side effects - short-term and long-term (

permanent

). The first type are short-term side effects, which by all indications are similar to the symptoms of an overdose in an adult.

The short-term side effects of nifedipine on the infant's body are presumably:

decrease or compensatory increase in heart rate; lowering blood pressure; cold extremities; blue nasolabial triangle; cold and clammy sweat; vomit; decreased muscle tone; severe lethargy of the child; loss of consciousness, convulsive seizures, etc. If the mother unknowingly does not notice such changes in the child's condition, continues to take nifedipine and simultaneously feed the child naturally, permanent side effects appear over time.
The persistent side effects of nifedipine on the baby's body are presumably: tachycardia (heart rate above normal (60 - 90 beats per minute)); increased blood pressure in relation to age standards; lagging behind in physical development (short stature, low muscle mass, etc.); the formation of acquired heart defects; exacerbation of congenital heart defects; blockade at various levels of the conduction system of the heart (a system that provides the correct sequence of contraction of various parts of the heart); rarely - mental retardation, etc.

Another important point should be mentioned. Due to the fact that in newborns the blood-brain barrier is not sufficiently developed, the neurological symptoms of an overdose will manifest themselves more strongly and earlier than others. In particular, this can be expressed in children who have had a difficult birth.

Neurological symptoms in children are:

headache; a state of stupor; lethargy; causeless crying, etc. In case of an urgent need to treat a nursing mother with nifedipine, there are two ways to solve this dilemma - replacing this drug with a less harmful one for the child or transferring the child to artificial nutrient mixtures for the duration of treatment. Each of these solutions has both its advantages and disadvantages. Therefore, the appropriate decision must be made only after carefully weighing all the pros and cons.

Advantages and disadvantages of replacing nifedipine with other drugs

Since nifedipine has two main effects - antihypertensive (

lowers blood pressure during hypertensive crises

) and antianginal (

reduces chest pain in angina pectoris

), then substitution drugs are also divided into two groups, according to the effects.

To lower blood pressure in nursing mothers, instead of nifedipine, the following can be used: furosemide; torasemide; indapamide; spironolactone; magnesium sulfate; drotaverine valerian (tablets), etc.

Advantages and disadvantages of transferring a child to artificial feeding during treatment with nifedipine

Which of the analogues of nifedipine is better?

All analogues of nifedipine are equally good. Therefore, in a pharmacy, you can safely choose the cheapest, however, given the required dose and type of drug (

regular or extended-release tablets

In practice, there are indeed cases when the same active substance in different medicines from different manufacturers has a different effect in strength. As a rule, in this case we are talking about original drugs and generic drugs. Original drugs are those drugs that were first invented, patented and put into mass production by one of the pharmacological companies. Generic drugs are copies of the original drug, and not always quite successful. It follows from this that original drugs are better than generics. However, this statement is true only during the first 10-20 years since the invention of the drug.

The explanation for this phenomenon is as follows. Together with the invention of a new medicinal substance (

original drug

) a pharmaceutical company acquires a patent and copyright for this drug. As a rule, according to this contract, none of the competing pharmaceutical companies has the right to put on the market an analogue of the original drug, called a generic, within 5 to 10 years from the date of registration of the patent. This time is provided by the state to the company that developed the drug in order to recoup the amount spent on research in this area. After this time, the copyright expires, and the pharmaceutical company that developed the drug is forced to reveal the formula of the drug and how it is produced to the world. However, in practice, only the main points of production are disclosed, and the first pharmaceutical company reserves some of the secrets, since this brings financial benefits. In order to bring the process of manufacturing generic drugs to the level of the original drug, some more time is required, on average another 5-10 years.

Thus, the following picture is obtained. The first 5-10 years, the original drug has no equal. The second 5 - 10 years, the original drug has copies that differ in quality. And only after a total of 10 - 20 years, generic drugs are equalized in quality with the original drug.

Original drugs, even after 20 years, usually retain their original cost, which is a kind of marketing ploy. Consumers continue to think that if a drug is more expensive, then it is better. However, in practice, in the case of nifedipine, the situation is different. More than 20 years have passed since its invention, and therefore all analogues of this drug do not differ in quality from the original. Therefore, when buying this product, it makes sense to save money and buy a less expensive product, since it will not be inferior in quality to the original.

There is still a possibility that the pharmacy will sell the patient a completely counterfeit drug, which, in fact, is not nifedipine. At best, instead of the active substance, there will be a placebo, and at worst, any other chemistry. However, counterfeiting nifedipine is not particularly profitable due to the fact that the price of this drug is quite low and will not bring big profits. In addition, a patient with a history of hypertension or coronary heart disease will immediately identify a fake, because he knows how the effect of this medicine should manifest itself, and, as a result, next time he will not buy a fake drug.

The risk of buying fake nifedipine is minimal today. Nevertheless, in order not to become a victim of a low-quality drug, it is recommended to buy medicines in large and time-tested pharmacy chains. These pharmacies work with regular suppliers and double-check medicines in order to prevent marriage and not lose reputation.

All of the above applies only to the tablet dosage form of nifedipine. These mechanisms do not apply to solutions for intravenous injections, since there is only one brand on the Russian market called Adalat. In other words, the problem of choosing the best analogue among nifedipine solutions disappears by itself, since this choice simply does not exist.

Do I need a prescription to buy nifedipine?

A prescription for the purchase of nifedipine is definitely needed. It is necessary for the most part for the patient himself, since it protects him from the undesirable effects of this drug when it is used arbitrarily.

A prescription is a legal document that holds a physician responsible for the effects of a particular drug prescribed by him to a particular patient. For a pharmacist, a prescription is also a kind of evidence that the patient is buying the drug not for his own reasons, but only after consulting a doctor. In the event that litigation arises between the doctor and the patient, the prescription can become a document that determines the guilt of one or the other party.

However, the legal aspects of the application of prescriptions are left aside when it comes to the health of the patient. Nifedipine is a strong drug in terms of its clinical effect. It should be dosed by a specialist, and not by the patient himself, since otherwise there is a risk of overdose. In some cases, an overdose of this drug can cause irreparable damage to the patient's health. In severe cases, it can be fatal.

Symptoms of an overdose of nifedipine are:

decrease in heart rate; occurrence of cardiac arrhythmias; signs of lowering blood pressure (weakness, dizziness, nausea, cold and sticky sweat, etc.); loss of consciousness; paradoxical chest pains (normally, the drug relieves such pains); convulsions, etc. The above symptoms are the result of the following effects of nifedipine on the body: decrease in the force of cardiac contraction; decrease in the speed of nerve impulse conduction along the conduction system of the heart; decrease in heart rate; expansion of arterioles, due to the relaxation of their smooth muscle membrane. In a correctly drawn up recipe, the required dose of the drug and the frequency of its administration are always indicated. Thus, the patient will receive treatment not at random, but on the recommendation of a specialist, which will protect him from taking an exorbitantly high dose.

Due to the fact that nifedipine, as mentioned above, produces a strong clinical effect, it has serious contraindications and restrictions for use in some groups of patients. For example, according to some data, the drug is completely contraindicated for pregnant women, and according to others, only in the first and second trimesters. For nursing mothers, this drug is prescribed only for health reasons. Children and young people under 18 years of age, this drug is not prescribed at all, since there is no evidence of its harmlessness for this category of patients today. For patients with decompensated heart failure, the drug is absolutely contraindicated.

The doctor knows these features of the drug and will not write a prescription for its purchase if nifedipine could potentially harm the patient or the fetus in the womb. Patients do not always know these features and therefore risk causing manifestations of side effects of the drug. As a result, we can conclude that having a prescription for the purchase of nifedipine in hand, the patient automatically falls into the category of patients for whom nifedipine is not contraindicated.

In practice, the situation is somewhat different. You can buy this drug without a prescription without any problems in almost any pharmacy. Pharmacists behind the counter often neglect the lack of a prescription in favor of profit, since the pharmaceutical business is one of the most profitable in the world, and the competition in it is quite high.

It is much easier for the patient to ask friends, neighbors, colleagues who had similar symptoms what they took to eliminate them than to make an appointment with a doctor, wait a certain time and get qualified help. Thus, the patient comes to the pharmacy, buys the first analogue of nifedipine that comes across among the numerous types and asks the pharmacist how to take it. At best, the pharmacist will suspect something is wrong and will not sell the drug without a proper prescription. In the worst case, the pharmacist gives the patient a standard regimen for taking nifedipine, not having the slightest idea about what disease this patient has and whether he needs the drug in principle. In addition, the pharmacist does not know what other drugs the patient is taking, which is certainly important in light of the fact that nifedipine can create highly undesirable combinations with certain cardiac drugs. As a result, all risks remain solely with the patient. In the event of a negative effect from taking the drug, the patient has no one to recover from except himself.

After all of the above, it is worth concluding that a prescription for the purchase of nifedipine is extremely important, even if the patient has taken it all his life and knows its effects and the required dosage. Such precautions are carried out, first of all, for the benefit of the patient himself.

Can nifedipine be given to children?

Prescribing nifedipine to children is prohibited by the manufacturers of this medicinal substance. The reason for the ban is the lack of reliable data on the safety of the drug when prescribing it to this category of patients.

A child's body is very different from an adult's body. This fact is easily confirmed by various age norms of physiological indicators of the body.

The following physiological parameters normally vary at different ages:

heart rate; arterial pressure; leukocyte formula (percentage of different types of white blood cells); hormonal profile; amplitudes of brain wave oscillations during various activities and much more. In other words, the child's body is not a stable system. Of course, this cannot be said about an adult organism, but, nevertheless, a child's organism is rebuilt and changes much faster in time than an adult. These changes occur under the influence of a huge number of factors, both internal and external. Any external influence, such as taking nifedipine, can make adjustments to a developing organism, and not always positive ones.

As you know, medicine is a science based on evidence. To use this or that medication, it is necessary to conduct numerous studies confirming the effectiveness of this drug, as well as its harmlessness, including in the long term. In the case of nifedipine, it was not possible to study its effect on the body of children. In order to achieve this goal, when testing the drug, it is necessary to expose a group of children to an undefined risk. In civilized countries, where almost all pharmaceutical research in the world is carried out, these studies will never be carried out for reasons of humanism and ethics. In connection with the foregoing, it remains unknown how the child's body will react to taking this medication once and for a long time.

Hypothetically, it can be assumed that a single dose of the lowest dose of nifedipine in a patient approaching the age of 18 years will have the same effects as in an adult. However, as the age of the patient decreases and the duration of the drug intake increases, its effects will become more and more unpredictable.

According to one hypothesis, after a few months of using this drug, the body's tolerance to this drug will come, as it happens in adults, but much faster. In other words, the body will get used to a certain dose and to achieve the effect it will have to be increased over and over again. However, with a sharp cessation of the use of the drug, a withdrawal syndrome will occur (

), manifested by the return of the previous symptoms, but with a more pronounced clinical manifestation.

According to another hypothesis, the use of nifedipine for more than several years in a row in childhood can affect the correct growth of the heart as an organ, as well as disrupt the blood pressure self-regulation system.

As a result of such an influence, the following deviations may form in the child's body: sinus tachycardia (heart rate above 90 per minute); constantly elevated blood pressure by more than 10 - 20 mm Hg in relation to normal values ​​\u200b\u200b(140/90 mm Hg); lagging behind in physical development due to a decrease in the pumping function of the heart; mental retardation; the appearance of acquired and aggravation of congenital heart defects; complete and incomplete blockade of the conduction pathways of the heart, etc.

In conclusion, I would like to add that the instructions for using the drug are not just included in the packaging of each drug. It contains a lot of useful information, including contraindications for use, written in such a way as to be clear to people without special education. Compliance with these warnings allows you to protect the health of the patients themselves and their loved ones.

Can I drink alcohol while taking nifedipine?

Drinking alcohol during treatment with nifedipine is highly discouraged. Alcohol enhances vasodilation (

dilation of blood vessels

) by enhancing the influence of the parasympathetic nervous system, which leads to a more pronounced decrease in blood pressure while taking nifedipine.

Nifedipine lowers blood pressure by relaxing the smooth muscles in the walls of peripheral blood vessels. The relaxation of the walls occurs due to a decrease in the rate of entry of calcium ions into the muscle cell.

Alcohol lowers blood pressure in other ways. First, it leads to a slowdown in neuromuscular transmission, due to which a drunk person develops some instability and loss of coordination of movements. However, this effect plays a small role in blood pressure regulation. Secondly, alcohol affects the central nervous system as well as the autonomic nervous system.

The effect of alcohol on the nervous system is carried out in several stages. According to various sources, these stages exist from two to five. However, for ease of understanding, only two steps will follow. The first stage is euphoric. In other words, for 15 - 30 minutes after drinking alcohol (

for some, this time can be both shorter and longer

) the mood of a person rises, all problems seem insignificant and distant, fears decrease. In people with mental illness, this stage is often absent, and it is replaced by irritability, aggressiveness, and cheeky behavior. The second stage is the stage of inhibition of the cortical processes of the brain. It is manifested by a decrease in mental abilities, relaxation, decreased coordination and, ultimately, falling asleep.

Both in the first and in the second stage of the action of alcohol, its effect on the body is also ensured through the autonomic nervous system. The autonomic nervous system is not controlled by desires. It is responsible for all reflex reactions that occur in the body, developed over many centuries of evolution and designed to ensure human survival in various environmental conditions. These reactions include dilation and constriction of the pupils, sweating, regulation of heart rate and blood pressure, the work of the glands of internal and external secretion, trembling in the cold, and much more.

The autonomic nervous system is divided into two parts:

sympathetic nervous system; parasympathetic nervous system. Sympathetic nervous system responsible for the manifestation of stress reactions that stimulate the body to protect, fight. In particular, it increases the heart rate, constricts arterioles, and increases blood pressure for better blood supply to the brain in the face of danger.
parasympathetic nervous system

has an opposite effect on the body, i.e., it calms, lulls, reduces the heart rate, etc.

These systems are in constant interaction, and the state of a person at a particular point in time depends on the tone of each of them. In the euphoric stage of alcohol intoxication, the influence of the sympathetic nervous system prevails, and in the second stage, the inhibitory one, the influence of the parasympathetic system increases. Moreover, it is important to note that alcohol greatly potentiates the influence of the parasympathetic system, resulting in an early falling asleep, accompanied by a decrease in blood pressure.

Thus, while taking nifedipine and alcoholic beverages, their actions are superimposed on each other and summarized. As a result, the decrease in blood pressure occurs faster and more pronounced. The heart rate, contrary to expectations, does not decrease, but increases, as a compensatory response to a strong decrease in blood pressure.

With severe alcohol intoxication and taking an average or large single dose, there is a high probability of developing a collapse (

decrease in blood pressure to zero values

), cardiogenic shock, acute

myocardial infarction

These conditions are critical and in a fairly large number of cases lead to death.

What if I have a headache after taking nifedipine?

Severe headaches immediately after taking nifedipine are a fairly common complication of this drug. However, this should not disturb the patients, since this pain is a consequence of the effectiveness of the drug, and to some extent it can be called quite expected.

It should be noted that such pain occurs mainly when taking nifedipine under the tongue or intravenously. When taking pills inside, the pains appear less often and are less painful. The reason for this difference is the speed of onset of the effect, which is maximum when administered intravenously, average when taken under the tongue, and minimal when taken orally.

Mechanism of action of nifedipine The point of application of the effect of nifedipine is muscle tissue. In particular, this drug most actively affects the heart muscle and the muscular membrane of peripheral vessels. When exposed to the heart, the vessels that feed it (coronary arteries) expand, the rhythm slows down, the strength of each individual contraction decreases, and the speed of the impulse through the conduction system of the heart slightly decreases. Thus, the supply of oxygen to the heart muscle increases and the rate of work of the heart decreases, allowing it some rest. Through the same mechanism, chest pains caused by ischemia (insufficient blood supply) of the myocardium (heart muscle) disappear.

The effect of nifedipine on the muscle layer of the vascular wall leads to its relaxation and, as a result, to an increase in the diameter of peripheral arteries. However, it should be noted that this effect extends only to arteries of various calibers, since their muscle layer is much thicker than that of veins. Expansion of peripheral vessels leads to a decrease in systemic arterial pressure. A decrease in blood pressure to some extent reduces the afterload on the heart, also reducing the intensity of its work.

Mechanism of headache As mentioned above, the decrease in blood pressure when using nifedipine is due to the expansion of peripheral vessels. The blood vessels of the head also dilate. With their sharp expansion, pain occurs. The occurrence of pain is the result of two mechanisms.

In the first case, the expansion of blood vessels leads to their stretching, which is signaled by baroreceptors (

pressure receptors

) vessel walls. With a sharp expansion, this impulse becomes more frequent, which is interpreted by the brain as pain.

In the second case, pain occurs as a consequence of the so-called "steal" phenomenon. Since the brain is located above all other organs, with a sharp decrease in blood pressure, for some time the brain receives less oxygen, since it is poorly supplied with blood. During this time, decay products accumulate in it and oxygen is not supplied, which together causes severe pain. As the blood supply to the brain improves, the pain subsides.

Advantages and disadvantages Undoubtedly, a headache when using nifedipine is far from the most pleasant feeling. However, on the other hand, it is not fatal, especially considering that it goes away on its own in 15 to 30 seconds. Pain is evidence that the drug is working.

If pain and some other unpleasant moments of using nifedipine are placed on one side of the scale, and the negative effect caused to the body by hypertension or myocardial ischemia is placed on the other (

for example, due to stable angina or atrial fibrillation

), it will definitely become clear that the latter is much more dangerous. Therefore, you should not give up nifedipine because of headaches. These pains do not have a significant negative effect on the brain and are quite a reasonable price for saving the patient's life in some critical situations.

What should I do if my child accidentally takes nifedipine?

When a child swallows a nifedipine tablet, first of all, you should ask someone who is nearby to call an ambulance, and provoke the child himself to vomit artificially by pressing a finger on the root of the tongue.

An overdose of nifedipine is quite easy to allow, without knowing the regimen and the exact dose to be taken. In addition, some medications taken concomitantly can slow down the excretion of nifedipine from the body, lead to its accumulation and, ultimately, to an overdose.

Among the medicines that, when taken in parallel with nifedipine, can cause an overdose of it, include:

cimetidine; ranitidine; diltiazem. Nifedipine is absolutely contraindicated in children up to 18 years of age, due to the lack of reliable data on its safety in this category of patients. Children are more likely to overdose with this drug than adults because their body weight is lower and their saturation limit is lower. It is believed that even one tablet of nifedipine with a minimum amount of the substance in it (10 mg) is enough to cause an overdose in a child of 3-5 years. Older children become supersaturated with 20 to 30 mg of nifedipine.

If, after taking the pill, parents do not notice changes in the child's condition for one or two hours, then this is not at all a reason for reassurance. Recently, nifedipine is being produced more and more often in the form of tablets coated with a special film coating, which provides a longer effect of the drug. Such tablets begin to act 2 hours after swallowing or more.

It is important to note that nifedipine is available in the form of a large number of analogues, each with its own commercial name. However, this should not mislead parents, since the active substance in them remains the same and still has a negative effect on the child's body.

Commercial (trade) names of nifedipine are:

adalat; calciguard retard; cordafen; cordaflex; cordipin; corinfar; nicardia; nifadil; nifebene; nifehexal; nifedex; nifedicap; nifedicor; nifecard; nifelate; nifesan; sanfidipin; fenigidin, etc. Symptoms of an overdose in a child are: dizziness; severe weakness; pallor and cyanosis of the skin; causeless crying; decrease, and then a compensatory increase in heart rate; lowering blood pressure; dyspnea; loss of consciousness; convulsions. Children under 3 years of age often cannot show that they have pain and explain what is bothering them. Therefore, they have a pronounced general weakness, pallor and cyanosis of the skin, nausea and vomiting, at first strong, and then more sluggish crying. In some cases, with a severe overdose, convulsions may occur.

First aid

Nifedipine poisoning is a life-threatening condition, so urgent and clear measures are required to remove the patient from it.

Action algorithm

Independently, with the help of relatives or an outsider, call an ambulance. Clearly explain to the dispatcher that the child was poisoned by pills and briefly describe his condition (conscious or not, vomiting, convulsions, etc.). This description automatically marks the call with a red code, which guarantees the arrival of a pediatric intensive care unit, a simple resuscitation, or the nearest available team as soon as possible. If the child is unconscious, then it must be laid on its side to prevent blockage of the airways by vomit or tongue. Place an emphasis (pillow, bundle of any fabric) under the neck and head. The head should be at a level with its physiological position. In this position, you should wait for an ambulance. It will not be possible to provide other assistance without special training and tools to the child. If the child is conscious, then you should immediately tilt it forward and press on the root of the tongue until vomiting occurs. Regardless of whether tablets were present in the vomit or not, the child should be given plain water to drink and vomiting should be repeated. This procedure must be continued until clean water appears in the vomit.

Prevention measures

In order to protect children from drug poisoning, you should:
keep all drugs out of reach of children; as they grow older, children should be taught that drugs can cause great harm if they are used ineptly; store especially dangerous drugs (affecting the brain, cardiovascular system, kidney and liver function, etc.) in a separate place, unknown to the child.

There are contraindications to the drugs mentioned in the text. It is necessary to read the instructions or consult with a specialist.

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