Nifedipine instructions for use, contraindications, side effects, reviews. Nifedipine: immediate reduction in blood pressure

Drug treatment of arterial hypertension involves the use of different groups of antihypertensive drugs. To gently and effectively lower blood pressure, they often resort to the use of blockers calcium channels. The most frequently prescribed drug in this group is Nifedipine.

Nifedipine is a drug that has a vasodilator and hypotensive effect. Belongs to the group of calcium channel blockers. It relieves vasospasm, while simultaneously performing a cardioprotective function. The drug has a fast action. Literally 20 minutes after taking it, a gentle decrease in blood pressure levels begins.

In what form is it produced and how much does it cost?

The drug is available in the form of tablets for oral administration and ointment for external application. The price of the drug depends on the patient’s place of residence and the pharmacy where it will be purchased. Approximate cost pharmaceutical product is given in the table.

These are only approximate prices at which you can purchase the drug Nifedipine.

Compound

One tablet contains 10 or 20 mg of the active substance nifedipine. As additional components, the drug contains milk sugar, microcrystalline cellulose, povidone 25, potato starch.

Nifedipine ointment contains 3 active substances: nifedipine, lidocaine and isosorbide dinitrate. Auxiliary components are trace elements from the Dead Sea. The drug is water-based and has a liquid consistency.

Therapeutic effect

Nifedipine tablets promote the expansion of blood (coronary, peripheral) vessels, thereby achieving a pronounced and persistent hypotensive effect. The drug helps reduce the tone of vascular smooth muscles and also relieves their spasm.

The drug has a slight effect on myocardial contractility, helping to reduce afterload. This subsequently leads to a decrease in its oxygen demand.

Note. Long-term use of the medication helps prevent the formation of new cholesterol plaques on the walls blood vessels. And this plays a huge role in the prevention of atherosclerotic disease.

Nifedipine ointment is widely used in proctology. It has antipruritic, regenerating, anti-inflammatory and anesthetic effects. With its help you can eliminate burning, swelling and discomfort in the perianal area. In addition, its effect is aimed at reducing hemorrhoids.

Indications and contraindications

At what pressure can this pharmaceutical product be used? Nifedipine tablets are intended to reduce high blood pressure in any degree of hypertension, as well as to relieve hypertensive crises.

Pills

The tablet form of the drug is prescribed to patients only if there are strict indications, which include:

In addition, it is advisable to use the drug for ischemic heart disease and atherosclerotic processes in peripheral arteries.

The tablet form should absolutely not be used by patients with the following diseases:

• tachycardia;
• cardiogenic shock;
• collapse;
• heart failure in the decompensation phase.

The medicine should not be used to treat persons under 18 years of age, hypotensive patients, and patients with idiopathic hypertrophic subaortic stenosis.

Nifedipine is prescribed with extreme caution to diabetics, pregnant women, patients with CHF, malignant course arterial hypertension and severe renal impairment. Under the careful supervision of a physician, treatment with this medication is carried out in patients undergoing hemodialysis sessions.

Ointment

Nifedipine gel emulsion is used to get rid of hemorrhoids accompanied by bleeding, anal fissures, prolapse of pathological nodes or their compression. In addition, the medicine has proven itself in the fight against perianal dermatitis.

Manufacturers do not provide information about contraindications to the use of ointment. The medication can be used during pregnancy.

Rules for treatment with Nifedipine

To avoid unwanted reactions, Nifedipine must be used correctly, in accordance with the instructions and advice of specialists.

Pills

The dosage of Nifedipine tablets is determined separately for each patient. In this case, the patient’s diagnosis, the severity of his condition, and the therapeutic response to the treatment are taken into account.

The initial dosage is 1 tablet (10 mg) 2-3 times/day. If there are no expected results from therapy, the dose may be doubled. The maximum permissible daily dosage is 40 mg.

Note. It is advisable to take the tablets at regular intervals.

Ointment

Nifedipine ointment is applied to the cleansed skin of the perianal area in a thin layer. To ensure that the product is absorbed faster, you can rub it in, but lightly, making massaging movements. After the manipulation, you need to lie down for at least a quarter of an hour so that the gel has time to take effect.

If the medicine does not lead to the development of side effects, then after a day it can be used rectally. To do this, insert a small amount of ointment into the anus with your finger or a sterile applicator. This should be done once first.

If this time no side effects occur, you can inject the medicine into the rectum 3-4 times a day. The duration of therapy is individual for each patient. But you should not stop treatment immediately after the disappearance of the unpleasant symptoms of hemorrhoids. To consolidate the results, it is recommended to extend it for another 2-3 days.

Is Nifedipine suitable for pregnant and lactating women?

Despite the fact that the tablet medication is contraindicated during pregnancy, doctors still sometimes resort to prescribing it. Increased uterine tone is a normal phenomenon exclusively during the 9th month of pregnancy. If it occurs earlier, especially in the first or second trimesters, this means that you need to act immediately. Nifedipine helps eliminate uterine hypertonicity.

It is advisable to prescribe the medicine to women in the 1-2 trimesters of pregnancy, but if there is a risk of premature onset of labor, then in the third. The dosage does not depend on the period, since in any case, the benefits of the drug for the expectant mother should exceed the potential risks to the fetus.

But first, Nifedipine is prescribed in a minimum dose - 10 mg (1 tablet) 4 times a day. The dosage can be doubled if there is no expected therapeutic effect. In case of urgent need, the amount of the drug taken per day can be increased to 60 mg (6 tablets).

Drink the product 20-30 minutes before meals, with a sufficient amount of still water. The duration of treatment is determined for each patient individually. It is not always possible to achieve an adequate therapeutic response from a pregnant woman’s body to the treatment, so its course can be prolonged by the attending physician.

Note. Often, expectant mothers taking Nifedipine are hospitalized. Thus, they will be monitored around the clock by medical personnel, which will significantly reduce the risk of complications from the therapy.

Nifedipine for breastfeeding

Nifedipine tablets are contraindicated for nursing mothers, since their components can penetrate into breast milk. If the use of the drug cannot be avoided, lactation must be stopped during treatment.

Nifedipine ointment can be used both during gestation and during breastfeeding.

Possible side effects

The use of Nifedipine in tablet form may cause side effects such as:

Long-term use of the medicine may have Negative influence and to work of cardio-vascular system. So, medicine can cause hypotension, asystole, bradycardia or tachycardia, angina pectoris. Sometimes side effects from the gastrointestinal tract may be alarming: nausea, diarrhea, heartburn attacks.

To change the drug, you must consult a general practitioner, family doctor or cardiologist.

Nifedipine is a selective antagonist of “slow” calcium channels, in its chemical structure which is a derivative of 1,4-dihydropyridine. It has a vasodilator, antianginal (anti-ischemic) and antihypertensive effect. Antagonists (blockers) of “slow” calcium channels are in the pharmacotherapeutic “top” of antihypertensive drugs. For many years now, cardiovascular patients have been treated with dihydropyridine derivatives, mostly short-acting ones. And if earlier these drugs could be seen as a real prospect, today doctors are no longer so optimistic. The way out of this situation was the creation of dihydropyridine derivatives long acting, which, along with ease of use, significantly increased the safety profile due to the gradual increase and stability of the concentrations of the active substance in the blood plasma. Data from randomized clinical trials indicate not only the pronounced antihypertensive activity of second-generation dihydropyridine derivatives, but also their positive effect on target organs and metabolic parameters. Nifedipine is available in both regular and extended-release forms. “Classic” nifedipine is produced mostly by domestic pharmaceutical factories, prolonged release is produced by the German pharmaceutical company STADA Arzneimittel.

The mechanism of action of nifedipine is based on a decrease in the flow of calcium ions into cardiomyocytes and smooth muscle cells of the coronary and peripheral arteries. Against the background of high dosages of nifedipine, calcium ions stop being released from intracellular depots. The drug “turns off” a certain number of functioning channels (which depends on the dose taken), without affecting the time of their activation, deactivation and recovery. Nifedipine desynchronizes the processes of contraction and excitation in the myocardium, mediated by troponin and tropomyosin, and in vascular smooth muscle tissue, mediated by calmodulin.

In recommended doses, the drug normalizes the flow of calcium ions through cell membranes, which is disrupted in some diseases, primarily in arterial hypertension. Stimulates blood circulation in the myocardium, improves blood supply to its areas affected by ischemia without the occurrence of the phenomenon of intercoronary steal, and activates the functioning of bypass (collateral) blood supply pathways. Increases the lumen of peripheral arteries, reduces overall peripheral vascular resistance, reduces the tone of the heart muscle and its need for oxygen, afterload, and increases the period of left ventricular diastole. It has virtually no effect on the sinoatrial and atrioventricular nodes, and does not exhibit antiarrhythmic activity. Stimulates blood flow in the renal tubules, promotes the removal of sodium from the body. The onset of therapeutic action is 20 minutes, its duration is 12-24 hours. The drug is well absorbed from the gastrointestinal tract (absorption rate - 92-98%), has moderate bioavailability (40-60%), which increases during meals. The prolonged form of nifedipine ensures a gradual release of the active substance into the systemic circulation. The half-life of the drug ranges from 3.7 to 17 hours (in patients with insufficient liver function it increases). It does not accumulate in the body. With long-term use (2-3 months), the effectiveness of the drug is partially lost due to the development of tolerance.

Nifedipine is available in tablets. They should be taken during or after meals with plenty of water. The initial dose of the drug is 20 mg 2 times a day. If there is no or weakly expressed result of pharmacotherapy, a twofold increase in the dose is allowed. In any case, you should not go beyond the daily maximum of 80 mg. For patients with liver failure, a more gentle daily dose of 40 mg is prescribed.

Pharmacology

Selective blocker of "slow" calcium channels, a derivative of 1,4-dihydropyridine. It has a vasodilating, antianginal and antihypertensive effect. Reduces the flow of calcium ions into cardiomyocytes and smooth muscle cells of the coronary and peripheral arteries; in high doses suppresses the release of calcium ions from intracellular stores. Reduces the number of functioning channels without affecting the time of their activation, inactivation and recovery.

It uncouples the processes of excitation and contraction in the myocardium, mediated by tropomyosin and troponin, and in vascular smooth muscles, mediated by calmodulin. In therapeutic doses, it normalizes the transmembrane current of calcium ions, which is disturbed in a number of pathological conditions, primarily in arterial hypertension. Does not affect the tone of the veins. Strengthens coronary blood flow, improves blood supply to ischemic areas of the myocardium without developing the “steal” phenomenon, and activates the functioning of collaterals. By dilating the peripheral arteries, it reduces the overall peripheral vascular resistance, myocardial tone, afterload, myocardial oxygen demand and increases the duration of diastolic relaxation of the left ventricle. It has virtually no effect on the sinoatrial and atrioventricular nodes and does not have antiarrhythmic activity. Increases renal blood flow, causes moderate natriuresis. The negative chrono-, dromo- and inotropic effects are overlapped by reflex activation of the sympathoadrenal system and an increase in heart rate in response to peripheral vasodilation.

The onset of the effect is 20 minutes, the duration of the effect is 12-24 hours.

Pharmacokinetics

Absorption is high (more than 92-98%). Bioavailability - 40-60%. Eating increases bioavailability. Has a “first pass” effect through the liver. Retard forms provide gradual release of the active substance into the systemic circulation. TC max 1.6-4.2 h, C max - 47-76 ng/ml. Communication with plasma proteins - 90%.

Penetrates through the BBB and placental barrier, excreted in breast milk.

Completely metabolized in the liver. The metabolism of the drug involves isoenzymes CYP3A4, CYP3A5 and CYP3A7.

T1/2 - 3.8-16.9 hours. In patients with liver failure, total clearance decreases and T1/2 increases. It is excreted in the form of inactive metabolites, mainly by the kidneys (80%) and bile (20%).

There is no cumulative effect. Chronic renal failure, hemodialysis and peritoneal dialysis do not affect pharmacokinetics. With long-term use (2-3 months), tolerance to the action of the drug develops.

Plasmapheresis may enhance elimination.

Release form

Extended-release tablets, film-coated, greyish-red in color, oblong, scored on both sides.

Excipients: microcrystalline cellulose - 51 mg, corn starch - 58.25 mg, lactose monohydrate - 36.2 mg, polysorbate 80 - 2 mg, magnesium stearate - 150 mcg, hypromellose - 2.4 mg.

Film shell composition: hypromellose - 4.2 mg, macrogol 6000 - 1.4 mg, talc - 700 mcg, titanium dioxide (E171) - 1 mg, red iron oxide dye (E172) - 200 mcg.

10 pieces. - blisters (5) - cardboard packs.
10 pieces. - blisters (10) - cardboard packs.

Dosage

Inside. The tablets should be swallowed whole, without chewing, during or after meals, with a small amount of water.

If liver function is impaired, the daily dose should not exceed 40 mg.

In elderly patients or patients receiving combination (antianginal or antihypertensive) therapy, lower doses are usually prescribed.

In case of liver dysfunction, in patients with severe impairment cerebral circulation the dose should be reduced.

The duration of treatment is determined in each case individually.

Overdose

Symptoms: headache, flushing of the facial skin, prolonged pronounced decrease in blood pressure, suppression of sinus node function, bradycardia, bradyarrhythmia. In severe poisoning - loss of consciousness, coma, metabolic acidosis, hypoxia, cardiogenic shock with pulmonary edema.

Treatment: in case of severe poisoning (collapse, depression of the sinus node), gastric lavage is performed and activated charcoal is prescribed. The antidote is calcium: slow intravenous administration of 10% calcium chloride or calcium gluconate at a dose of 0.2 ml/kg (but not more than 10 ml) over 5 minutes is indicated; if ineffective, repeated administration is possible under the control of the content of calcium ions in the blood serum, with If symptoms resume, you can switch to a constant infusion at a rate of 0.2 ml/kg/h, but not more than 10 ml/h.

With a pronounced decrease in blood pressure - intravenous administration of dopamine or dobutamine.

For conduction disorders - atropine, isoprenaline or an artificial pacemaker.

With the development of heart failure - intravenous administration of strophanthin.

Catecholamines should be used only when there is a threat to life (due to their reduced effectiveness, a high dosage is required, which increases the risk of developing arrhythmia). It is recommended to monitor the concentration of glucose in the blood (insulin release may decrease) and electrolytes (potassium ions, calcium ions).

Hemodialysis is ineffective.

Interaction

The severity of the decrease in blood pressure increases with the simultaneous use of nifedipine with other antihypertensive drugs, nitrates, cimetidine, ranitidine (to a lesser extent), inhalational anesthetics,
diuretics and tricyclic antidepressants.

Under the influence of nifedipine, the concentration of quinidine in the blood plasma is significantly reduced. Increases the concentration of digoxin in the blood plasma, and therefore the clinical effect and the content of digoxin in the blood plasma should be monitored.

Rifampicin is a powerful inducer of the CYP3A4 isoenzyme. When used together with rifampicin, the bioavailability of nifedipine is significantly reduced and, accordingly, its effectiveness is reduced. The use of nifedipine in combination with rifampicin is contraindicated. In combination with citrates, tachycardia and the antihypertensive effect of nifedipine are enhanced. Calcium supplements may reduce the effect of slow calcium channel blockers. When used together with nifedipine, the anticoagulant activity of coumarin derivatives increases.

It can displace drugs characterized by a high degree of binding (including indirect anticoagulants- coumarin and indandione derivatives, anticonvulsants, quinine, salicylates, sulfinpyrazone), as a result of which their concentrations in the blood plasma may increase. Suppresses the metabolism of prazosin and other alpha-blockers, as a result of which the antihypertensive effect may be enhanced.

Procainamide, quinidine, and other drugs known to prolong the QT interval enhance the negative inotropic effect and may increase the risk of significant QT prolongation.

Concomitant use with magnesium sulfate in pregnant women may cause blockade of neuromuscular synapses.

Inhibitors of the cytochrome P450 3A system, such as macrolides (for example, erythromycin), fluoxetine, nefazodone, protease inhibitors (for example, amprenavir, indinavir, nelfinavir, ritonavir or saquinavir), antifungals (ketoconazole, itraconazole or fluconazole) lead to increased concentrations of nifedipine in blood plasma. Taking into account the experience with the use of the “slow” calcium channel blocker nimodipine, the following interactions with nifedipine cannot be excluded: carbamazepine, phenobarbital - a decrease in the concentration of nifedipine in the blood plasma; quinupristin, dalfopristin, valproic acid - increase the concentration of nifedipine in the blood plasma.

Nifedipine should be prescribed with caution concomitantly with disopyramide and flecainide due to a possible increase in inotropic effect.

Nifedipine inhibits the elimination of vincristine from the body and may cause increased side effects; if necessary, reduce the dose of vincristine.

Grapefruit juice suppresses the metabolism of nifedipine in the body, and therefore their simultaneous use is contraindicated.

Side effects

The frequency of these side effects is indicated in accordance with the WHO classification: very often - more than 10%; often - more than 1% and less than 10%; infrequently - more than 0.1% and less than 1%; rarely - more than 0.01% and less than 0.1%; very rarely - less than 0.01%, including isolated cases.

From the cardiovascular system: often - peripheral edema (feet, ankles, legs), symptoms of vasodilation (redness of the facial skin, feeling of heat); infrequently - tachycardia, rapid heartbeat, marked decrease in blood pressure, fainting; in some cases - chest pain (angina) up to
development of myocardial infarction, development or worsening of chronic heart failure, arrhythmia.

From the nervous system: very often - headache; often - dizziness, drowsiness; uncommon - asthenia, sleep disturbance (including insomnia), nervousness, increased fatigue, dysesthesia, tremor, mood lability.

From the digestive system: often - nausea; uncommon - gastrointestinal and abdominal pain (pain in the stomach and intestines), diarrhea, constipation, dry oral mucosa, increased appetite; rarely - gum hyperplasia (bleeding, pain, swelling). With long-term use: infrequently - liver dysfunction (intrahepatic cholestasis, increased activity of "liver" transaminases), rarely - jaundice; in some cases - insufficiency of the cardiac sphincter.

From the outside respiratory system: infrequently - shortness of breath, rarely - pulmonary edema (difficulty breathing, cough, wheezing).

From the musculoskeletal system: rarely - arthralgia, swelling of the joints, myalgia, muscle cramps.

From the hematopoietic organs: rarely - anemia, leukopenia, thrombocytopenia, thrombocytopenic purpura; very rarely - asymptomatic agranulocytosis.

From the urinary system: uncommon - increased daily diuresis, deterioration of renal function (in patients with renal failure).

Allergic reactions: often - erythema; rarely - itchy skin, urticaria, exanthema, photosensitivity, autoimmune hepatitis; infrequently - angioedema; in some cases - toxic epidermal necrolysis.

Other: rarely - visual impairment (including transient loss of vision against the background of the maximum concentration of nifedipine in the blood plasma), eye pain, hyperglycemia, gynecomastia (in elderly patients; completely disappearing after discontinuation of the drug), galactorrhea, erectile disfunction, weight gain, chills, nosebleeds, nasal congestion.

Indications

• chronic stable angina (angina pectoris);
• vasospastic angina (Prinzmetal's angina);
• arterial hypertension (in monotherapy or in combination with other antihypertensive drugs);
• Raynaud's disease and syndrome.

Contraindications

• arterial hypotension (systolic blood pressure below 90 mmHg);
• cardiogenic shock;
• collapse;
• severe aortic or subaortic stenosis;
• acute heart failure;
• chronic heart failure in the stage of decompensation;
• unstable angina;
• acute period of myocardial infarction (during the first 4 weeks);
• hypertrophic obstructive cardiomyopathy;
• sick sinus syndrome;
• AV blockade II-III degree;
• pregnancy (up to 20 weeks);
• lactation period;
• age under 18 years (the effectiveness and safety of use have not been studied);
• hypersensitivity to nifedipine or other components of the drug.

The drug contains lactose and is therefore contraindicated for use in patients with rare hereditary diseases of lactose intolerance, lactase deficiency, and glucose-galactose malabsorption.

With caution: mitral stenosis, severe bradycardia or tachycardia, chronic heart failure, severe cerebrovascular accidents, myocardial infarction with left ventricular failure, gastrointestinal obstruction (for sustained-release forms), liver failure, chronic renal failure (especially patients on hemodialysis - high risk of excessive and unpredictable decrease in blood pressure), simultaneous use of beta-blockers and cardiac glycosides, pregnancy (after 20 weeks), old age.

Features of application

Use during pregnancy and breastfeeding

There have been no controlled studies of the use of Nifedipine in pregnant women.

Animal tests have shown the presence of embryotoxicity, placentotoxicity, fetotoxicity and teratogenicity when taking nifedipine during and after the period of organogenesis.

Based on the available clinical data, it is impossible to judge the specific perinatal risk. However, there is evidence of an increased likelihood of perinatal asphyxia, cesarean section, premature birth and intrauterine growth retardation. It is unclear whether these cases are a consequence of the underlying disease (arterial hypertension), the treatment being administered, or a specific effect of the drug Nifedipine. The available information is insufficient to exclude the possibility of side effects that pose a danger to the fetus and newborn. Therefore, the use of Nifedipine after the 20th week of pregnancy requires a careful individual assessment of the risk-benefit ratio for the patient, fetus and/or newborn and can only be considered in cases where other methods of therapy are contraindicated or ineffective.

Blood pressure should be carefully monitored in pregnant women when using Nifedipine simultaneously with intravenous magnesium sulfate due to the possibility of an excessive decrease in blood pressure, which poses a danger to both the mother and the fetus and/or newborn.

Nifedipine is contraindicated during lactation as it is excreted in breast milk. If Nifedipine therapy is absolutely necessary, it is recommended to stop breastfeeding.

Use for liver dysfunction

Use for renal impairment

Use in children

special instructions

During the treatment period, you must refrain from drinking alcohol.

Despite the absence of withdrawal syndrome with slow calcium channel blockers, a gradual dose reduction is recommended before stopping treatment.

The simultaneous administration of beta-blockers must be carried out under conditions of careful medical supervision, since this may cause an excessive decrease in blood pressure, and in some cases, aggravation of heart failure. During treatment, positive results are possible with direct Coombs test and laboratory tests for antinuclear antibodies.

Regularity of treatment is important, regardless of how you feel, since the patient may not feel the symptoms of arterial hypertension.

The diagnostic criteria for prescribing the drug for vasospastic angina are: classical, clinical picture accompanied by characteristic changes in the electrocardiogram (ST segment elevation); occurrence of ergometrine-induced angina or spasm coronary arteries; identification of coronary spasm during angiography or identification of an angiospastic component, without confirmation (for example, with a different voltage threshold or with unstable angina, when electrocardiogram data indicate transient angiospasm).

For patients with severe hypertrophic cardiomyopathy, there is a risk of increased frequency, severity and duration of angina attacks after taking nifedipine; in this case, discontinuation of the drug is necessary.

In patients on hemodialysis with high blood pressure, irreversible renal failure, and a decrease in circulating blood volume, the drug should be used with caution, since a sharp drop in blood pressure may occur.

Patients with impaired liver function are closely monitored and, if necessary, the dose of the drug is reduced and/or other dosage forms of nifedipine are used.

It should be borne in mind that angina pectoris may occur at the beginning of treatment, especially after recent abrupt withdrawal of beta-blockers (the latter are recommended to be withdrawn gradually).

If during therapy the patient requires surgical intervention under general anesthesia, it is necessary to inform the surgeon-anesthesiologist about the nature of the therapy being performed.

When spectrophotometrically assessed, nifedipine may lead to incorrect detection of increased levels of vanillyl-mandelic acid in the urine; it does not affect studies using high-performance liquid chromatography.

During in vitro fertilization, in some cases, blockers of “slow” calcium channels caused changes in the head part of the sperm, which could lead to dysfunction of the sperm. In cases in which repeated in vitro fertilization failed for unknown reasons, calcium channel blockers, including nifedipine, were considered a possible cause of failure.

Impact on the ability to drive vehicles and operate machinery

During treatment, care must be taken when managing vehicles and engaging in other potentially hazardous activities that require increased concentration and speed of psychomotor reactions.

This medicine has many benefits. One of them is the possibility of using it both in emergency and chronic conditions. During an attack of chest pain, a tablet of the drug is placed under the tongue and chewed, after which the pain goes away after 5 - 15 minutes. Long-term use of the drug is encouraged for stable angina pectoris. In this case, predominantly extended-release forms of the drug are used.

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

It should also be noted that nifedipine long time was 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 effect, this drug was used to carry a pregnancy to term in case of an acute threat of miscarriage. Currently, there are more advanced drugs used for this purpose, which have a targeted effect and less pronounced side effects, however, in some cases, preference is given to nifedipine due to its effects on the cardiovascular system.

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

Patients under 18 years of age this drug can be prescribed only in exceptional cases, since there is currently no evidence of its safety for this category of patients. In other words, it is not known whether nifedipine will act on children's body similar to an adult or in some other way.

The same dilemma arises for pregnant women. According to some data, 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 extent of this probability has been little studied, since the 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 secretions of the mammary glands, nursing mothers are recommended to switch the child to artificial feeding during treatment or resort to the use of other antihypertensive or antianginal drugs.

Types of medication, commercial names of analogues, release forms

• dragee;
• pills;
• solution for intravenous drip administration.

Nifedipine tablets come in two types - short-acting and extended-acting. Pills short acting 10 and 20 mg are used mainly when necessary to reduce high blood pressure or get rid of chest pain during rare attacks in relatively healthy patients. In such cases, taking this drug is episodic. Extended-release 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 only 3 to 1 time per day. Moreover, such tablets are available in a wide variety of doses from 20 to 60 mg, which allows the treatment of each patient to be most accurately adjusted.

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

Nifedipine exists on pharmaceutical market under the following commercial names:

• Corinfar;
• Cordaflex;
• Nifesan;
• Sanfidipin;
• Nifelate;
• Nifecard;
• Cordipin;
• Nifedicor;
• Nifedex;
• Nifehexal;
• Nifadil;
• Nicardia;
• Adalat et al.

Manufacturers of nifedipine

The mechanism of therapeutic action of the drug

In view of the above, we can conclude that the bioavailability of the drug ( the ratio of the active substance that has reached its goal to the entire administered single dose) equals on average 40 - 60%. The main losses of the drug occur during the first passage through the liver, before the bulk of it has time to contact plasma proteins.

The point of application of this drug is the plasma membrane of muscle cells. Nifedipine blocks the channels for calcium ions to enter the cell, as a result of which calcium does not penetrate into it. Are slowing down chemical reactions, responsible for the development of muscle contraction. The drug has the most active effect on cardiomyocytes ( heart muscle cells) and smooth muscle of arterial blood vessels. Nifedipine has no effect on veins, since their muscle layer is weakly expressed. In addition, in medium and large doses the drug has a strong antispasmodic effect on the smooth muscles of internal organs. In this regard, nifedipine was used for a long time in obstetrics and nephrology. In obstetrics – when there is a threat of miscarriage, due to increased tone uterus, and in nephrology - for relieving renal colic. Today, 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 ( reduces the force of heart contraction);
• negative chronotropic ( reduces heart rate);
• negative dromotropic ( reducing the speed of conduction nerve impulse through the conduction system of the heart).

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

Nifedipine has only one effect on blood vessels – dilation, but this leads to many positive effects.

The vasodilatory effects of nifedipine are as follows:

• reducing afterload on the heart, increasing its efficiency;
• elimination of hypertension in the pulmonary circulation - reduction of shortness of breath due to an increase in the diameter of the bronchi;
• improvement of cerebral circulation;
• improvement of renal excretory function due to expansion 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, one cannot conclude that this medicine is harmless for pregnant women. Unfortunately, no studies have been conducted to examine this issue. Therefore, pregnant women are recommended to take the drug only after consulting a doctor first. According to clinical observations, its use in the third trimester of pregnancy in standard doses is relatively safe.

Besides everything else, active substance penetrates 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 nutritional formulas throughout the treatment. Otherwise, doses that are normal for the mother may turn out to be excessive for the child and cause an overdose in his small body with all the ensuing complications.

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

Interaction of nifedipine with magnesium salts ( for example, magnesium sulfate) is also dangerous due to the risk sharp fall blood pressure. In addition, there is a high probability of developing a neuromuscular block, expressed by severe weakness, imprecision of movements, shortness of breath, difficulty swallowing, etc. In connection with the above, the use of magnesium sulfate is primarily recommended for pregnant women with preeclampsia and eclampsia. If the effect is weak, the use of nifedipine is contraindicated. Instead, loop diuretics are used ( diuretics such as furosemide, torsemide, etc.), ACE inhibitors (angiotensin converting enzyme, such as captopril, enalaprilat) and other methods, but for a short time. The only way stopping the progression of preeclampsia and eclampsia is childbirth.

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

When nifedipine and tacrolimus (an immunosuppressant) are used together, 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 can reduce 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 because the latter increases the activity of liver enzymes, thereby converting almost all nifedipine on its first pass through the liver.

Approximate cost of the medicine

Cost of nifedipine in various regions of the Russian Federation

Can nifedipine be taken during pregnancy?

This restriction has good reasons. In the first and second trimester of pregnancy, the formation of future vital organs and systems occurs in the fetus’s body. Any influence, be it a medicine, household chemicals or simply 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 an error can lead to more or less serious anomalies of physical or mental development. For this reason, it is recommended to abstain from all medications during the first 6 months of pregnancy. systemic action and use them only when absolutely necessary, when the expected benefit outweighs the potential harm. Medicines local application do not create high concentrations of the active substance in the blood, therefore they are practically harmless to the fetus.

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

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

Despite the fact that nifedipine penetrates the placenta in very low concentrations and practically cannot harm the fetus, no one undertakes to claim the opposite until special studies are conducted on pregnant women. However, due to the fact that such research is inhumane, the likelihood of it being carried out is close to zero. Thus, the data that science currently has regarding the safety of nifedipine for pregnant women is unlikely to be replenished in the near future, so we will have to be content with what we have.

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 precise dosage. When accidentally taking a high dose, the first thing to do is to greatly reduce your blood pressure. For any person, this threatens a deterioration in health, up to loss of consciousness due to oxygen starvation brain. For pregnant women, the risks double, since with low blood pressure not only the mother’s body suffers, but also the fetus, which receives less oxygen and nutrients due to deterioration of blood supply to the placenta.

When deciding whether or not a pregnant woman should take nifedipine, she should determine 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 select 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 be carried out not by the woman herself, but by her attending physician. In this case, nifedipine can be successfully replaced with diuretics ( furosemide, torsemide, 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 chest pain ( Such conditions may well occur in young mothers with congenital or acquired heart defects), then nifedipine can certainly be replaced with nitro drugs such as isosorbide dinitrate ( cardicket), isosorbide mononitrate ( allowed only in the second and third trimester) and etc.

If there is a threat of premature birth, 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 combination therapy with other drugs that reduce uterine tone. There are also plenty of such funds. The most prominent representatives are antispasmodics ( baralgin, papaverine, drotaverine, mebeverine, etc.), drugs that reduce uterine activity ( magnesium sulfate, magnesium B-6, etc.), beta adrenergic agonists ( partusisten, terbutaline, etc.).

To summarize 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 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 cross the blood-brain barrier. However, in people who have had a serious traumatic brain injury in the past or have certain mental illness, this barrier may be weakened. This allows more of the drug to enter the brain, which often causes side effects from the central nervous system.

So, distributed throughout the body, nifedipine enters the mammary glands and directly into their secretion - breast milk. Considering that bioavailability ( the proportion of a substance that has an effect on peripheral tissues in relation to the entire administered dose) of this medicine equals 40 - 60% can enter the child’s body through milk during one average feeding ( 100 - 200 ml) 1:40 to 1:80 adult dose. Considering that the weight of a child is on average 10-15 times less than the weight of an adult, such a dose may seem relatively small for the clinical effect of nifedipine to manifest 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 survive 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 baby's tissues are extremely sensitive to any kind of biological and chemical signals. Therefore, the dose of nifedipine, which according to all calculations 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 is short-term side effects, which in all respects are similar to the symptoms of an overdose in an adult.

Short-term side effects of nifedipine on the baby's body are presumably:

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

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

• tachycardia ( heart rate is higher than normal values(60 – 90 beats per minute));
• elevated blood pressure relative to age standards;
• retardation in physical development ( short stature, low muscle mass, etc.);
• formation of acquired heart defects;
• worsening congenital heart defects;
• blockade on various levels conduction system of the heart ( a system that ensures the correct sequence of contractions of different parts of the heart);
• rarely – mental retardation, etc.

Neurological symptoms in children are:

• headache;
• state of stupefaction;
• lethargy;
• causeless crying, etc.

Advantages and disadvantages of replacing nifedipine with others medicines

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

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

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

Which nifedipine analogue is better?

In practice, there are indeed cases when the same active substance in different medicines from different manufacturers it has different effects. 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 from the moment the drug is invented.

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 a given drug. As a rule, according to this contract, none of the competing pharmaceutical companies has the right to market an analogue of the original drug, called a generic, for 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 scientific developments in this area. After this time, the copyright expires, and the pharmaceutical company that developed the drug is forced to disclose the drug formula and methods of its production to the whole world. However, in practice, only the main aspects of production are disclosed, and the first pharmaceutical company retains some of the secrets, since this brings financial benefits. In order to bring the manufacturing process of generic drugs to the level of the original drug, it takes some more time, on average another 5 - 10 years.

Thus, the following picture is obtained. For the first 5 - 10 years, the original drug has no equal. During the second 5 - 10 years, copies of the original drug appear, varying in quality. And only after a total of 10 - 20 years do generic drugs become equal in quality to the original drug.

Original drugs, even after 20 years, as a rule, retain their original cost, which is a kind of marketing ploy. Buyers continue to think that if a drug is more expensive, it means it is better. However, in practice, this is not the case with nifedipine. 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 purchasing this tool 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 also a possibility that the pharmacy will sell the patient a completely counterfeit drug, which in fact is not nifedipine. IN best case scenario 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 much profit. In addition, a patient with experience of hypertension or coronary heart disease will immediately identify a fake, since he knows how the effect of this medicine should manifest itself, and, as a result, will not buy a counterfeit drug next time.

The risk of buying counterfeit nifedipine is minimal today. However, in order to avoid becoming a victim of a low-quality drug, it is recommended to buy medications from large, time-tested pharmacy chains. These pharmacies work with regular suppliers and double-check medications to prevent defects and loss of reputation.

All of the above applies only to the tablet dosage form of nifedipine. These mechanisms do not apply to solutions for intravenous infusions, 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?

The recipe is legal document, according to which the doctor is responsible for the effects of a particular drug prescribed to a specific patient. For a pharmacist, a prescription is also a kind of evidence that the patient does not buy the drug for his own reasons, but only after consulting with a doctor. If litigation arises between a doctor and a patient, a prescription can become a document determining the guilt of one or the other party.

However, the legal aspects of using prescriptions remain aside when it comes to the patient’s health. Nifedipine is a drug with a strong clinical effect. Its dosing should be done 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:

• the occurrence of heart rhythm disturbances;
• signs of decreased blood pressure ( weakness, dizziness, nausea, cold and sticky sweat, etc.);
• loss of consciousness;
• paradoxical chest pain ( Normally, the drug relieves such pain);

• decreased force of heart contraction;
• decrease in the speed of nerve impulse transmission through the conduction system of the heart;
• decreased heart rate;
• dilation of arterioles due to 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 limitations for use in certain 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. This drug is prescribed to nursing mothers only for health reasons. This drug is not prescribed to children and young people under 18 years of age, since there is currently no evidence of its harmlessness for this category of patients. 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 side effects of the drug. As a result, we can conclude that having a prescription for 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 ignore the lack of a prescription for the sake of profit, since pharmaceutical business is one of the most profitable in the world, and the competition in it is quite strong.

It is much easier for a patient to ask friends, neighbors, and co-workers who experienced similar symptoms, what they took to eliminate them, than to make an appointment with a doctor, wait a certain time and receive qualified help. Thus, the patient comes to the pharmacy, buys the first analogue of nifedipine he 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 of nifedipine, without having the slightest idea about what disease the patient has and whether he needs the drug in principle. In addition, the pharmacist does not know what other medications the patient is taking, which is of course important in light of the fact that nifedipine can create extremely undesirable combinations with some cardiac medications. 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 been taking 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 prescribed to children?

A child's body differs in many ways from an adult's body. This fact is easily confirmed by various age standards physiological indicators of the body.

The following physiological indicators normally vary at different ages:

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

As you know, medicine is an evidence-based science. To use a particular 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 a drug, it is necessary to expose a group of children to an unknown 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 above, it remains unknown how the child’s body will react to taking this medication once and over a long period of time.

Hypothetically, it can be assumed that one-time appointment The lowest dose of nifedipine in a patient approaching 18 years of age will have the same effects as in an adult. However, as the patient's age decreases and the duration of use of the drug increases, its effects will become more and more unpredictable.

According to one hypothesis, after a few months of using this drug, the body will develop tolerance to this drug, as happens in adults, but much faster. In other words, the body will get used to a certain dose and to achieve an effect it will have to be increased over and over again. However, if you abruptly stop using the drug, withdrawal syndrome will occur ( rebound), manifested by the return of 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 proper growth of the heart as an organ, as well as disrupt the system of self-regulation of blood pressure.

As a result of this 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 mmHg relative to normal values (140/90 mm Hg. Art.);
• retardation in physical development due to decreased pumping function of the heart;
• mental retardation;
• the appearance of acquired and worsening congenital heart defects;
• complete and incomplete blockades of the conduction pathways of the heart, etc.

Can I drink alcohol while being treated with nifedipine?

Nifedipine lowers blood pressure by relaxing the smooth muscle in the walls of peripheral blood vessels. 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, which causes a drunk person to experience some instability and loss of coordination. However, this effect plays a small role in regulating blood pressure. Secondly, alcohol affects the central nervous system as well as the autonomic nervous system.

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

Both in the first and second stages of the action of alcohol, its effect on the body is also achieved through the autonomic nervous system. Vegetative nervous system uncontrollable by desires. It is responsible for all reflex reactions occurring in the body, developed over many centuries of evolution and designed to ensure human survival in different conditions environment. Such reactions include dilation and constriction of the pupils, sweating, regulation of heart rate and blood pressure, the functioning of the endocrine and exocrine glands, shivering 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 a counter-directional effect on the body, i.e. it calms, lulls, reduces heart rate, etc.

These systems are in constant interaction, and the state of a person at a particular moment 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 stage, the influence of the parasympathetic system increases. Moreover, it is important to note that alcohol strongly potentiates the influence of the parasympathetic system, resulting in rapid falling asleep, accompanied by a decrease in blood pressure.

Thus, when taking nifedipine and alcoholic drinks their actions overlap and add up. 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 reaction to a strong decrease in blood pressure.

With severe alcohol intoxication and taking a medium or large single dose, there is a high probability of developing collapse ( reduction 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 sublingually or intravenously. When taking tablets orally, pain appears less frequently and is 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 layer. 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, and the speed of impulse passage 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, chest pain caused by ischemia disappears ( insufficient blood supply) myocardium ( heart muscle).

The effect of nifedipine on the muscle layer vascular wall leads to its relaxation and, as a consequence, to an increase in the diameter of the peripheral arteries. However, it should be noted that this effect applies only to arteries of various calibers, since their muscle layer is much thicker than that of veins. Peripheral vasodilation leads to a decrease in systemic blood 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, a decrease in blood pressure when using nifedipine occurs due to dilation of peripheral vessels. The blood vessels of the head also dilate. When they suddenly expand, pain occurs. The occurrence of pain is a consequence of two mechanisms.

In the first case, vasodilation 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 “stealing” phenomenon. Since the brain is located above all other organs, with a sharp decrease in blood pressure, the brain does not receive enough oxygen for some time, 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 we put pain and some other unpleasant aspects of using nifedipine on one side of the scale, and on the other side – the negative effect caused to the body by hypertension or myocardial ischemia ( for example, due to stable angina or atrial fibrillation), then it will definitely become clear that the latter is much more dangerous. Therefore, you should not refuse nifedipine due to headaches. These pains do not have a significant negative effect on the brain and are a very reasonable price to pay for saving the patient’s life in some critical situations.

What to do if a child accidentally takes nifedipine?

It is quite easy to overdose on nifedipine without knowing the regimen and the exact dose that needs to be taken. In addition, some medications taken in parallel can slow down the elimination of nifedipine from the body, lead to its accumulation and, ultimately, to an overdose.


Medicines that, when taken in parallel with nifedipine, can cause an overdose 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 to reassure. Recently, nifedipine has been increasingly produced in the form of tablets coated with a special film coating, which ensures a longer-lasting effect of the drug. Such tablets begin to act 2 hours or more after swallowing.

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;
• calcigard retard;
• cordafen;
• Cordaflex;
• cordipine;
• Corinfar;
• nicardia;
• nifadil;
• nifebene;
• nifehexal;
• nifedex;
• nifedicap;
• nifedicor;
• Nifecard;
• nifelate;
• nifesan;
• sanfidipine;
• phenigidine, etc.

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

First aid

Action algorithm

• Call an ambulance yourself, with the help of loved ones or a stranger. Clearly explain to the dispatcher that the child was poisoned by pills and briefly describe his condition (conscious or not, vomiting, convulsions, etc.). Such a description automatically marks the call with a red code, which guarantees the arrival of a pediatric intensive care unit, simple intensive care unit, or the nearest available team as soon as possible.
• If the child is unconscious, he should be placed on his side to prevent blockage. respiratory tract vomit or tongue. Place a support (pillow, roll of any fabric) under your neck and head. The head should be level with its physiological position. In this position, you should wait for an ambulance. It will not be possible to provide any other assistance to a child without special training and tools.
• If the child is conscious, then you should immediately tilt him forward and press on the root of the tongue until vomiting occurs. Regardless of whether tablets were present in the vomit or not, you should give the child plain water and induce vomiting again. This procedure must be continued until there is clean water in the vomit.

Prevention measures

• keep all medications out of reach of children;
• as they grow older, children should be explained that medications can cause great harm if used inappropriately;
• store separately dangerous drugs (affecting the brain, cardiovascular system, renal and hepatic function, etc.) in a separate place, unknown to the child.

Many people ask questions about what the drug Nifedipine looks like and instructions for use, at what pressure it is used. The medication was used back in the Soviet Union in the treatment of hypertension and other heart diseases. IN modern cardiology Nifedipine 10 mg is one of the most popular drugs.

Brief description of the effect on the body

The drug Nifedipine belongs to the group of calcium channel blockers. It slows down the passage of calcium ions into the cells of the heart and the vessels that feed it. Suppression of the electrical activity of cardiac muscle cells is observed. As a result, the lumen of the heart vessels increases and blood pressure decreases.

In addition to the antihypertensive effect, normalization of heart rate occurs. With myocardial infarction, there is a decrease in pain sensitivity. Increased coronary blood flow reduces the load placed on the heart muscle. Thus, the organ’s need for oxygen decreases and its functioning is normalized.

With long-term use, more than 2-3 months, the effectiveness decreases, as addiction to the drug occurs. Tablets are the most optimal shape use, since the medicine quickly dissolves in the stomach and is absorbed 100%. After passing through the digestive tract, the medication enters the liver. Due to the transformation in this organ, the bioavailability of the drug is highest.

The maximum amount accumulates in the blood 3 hours after administration. The main part of it is excreted by the kidneys without causing any changes. There is no accumulation in the body.

When can and cannot be used?

Based on the mechanism of action of the drug on the body, we can conclude that taking Nifedipine is recommended in case of poor oxygen delivery to the heart and cardiac muscle. There are several such diseases:

• hypertonic disease, including;
• angina pectoris, coronary heart disease;
• hypertrophic cardiomyopathy;
• pulmonary hypertension;
• broncho-obstructive syndrome.

Based on the mechanism of action of the drug, it is possible to identify diseases for which taking Nifedipine tablets is strictly prohibited. Among them:

1. Allergic reactions to the drug.
2. Myocardial infarction for up to 8 days.
3. Cardiogenic shock (severe and acute failure strength of heart contractions, complication of myocardial infarction).
4. Unstable angina.
5. Tachycardia.
6. Low blood pressure.
7. Severe aortic stenosis (narrowing of the aortic lumen).
8. Decompensated heart failure.
9. Pregnancy and lactation period.
10. Breastfeeding stops completely during the period of treatment with the drug. There is a risk of passing through the placenta and into breast milk.

Particular care should be taken when prescribing treatment for liver and kidney diseases. Transformation and excretion pass through these organs, therefore, when they are deficient, metabolites remain and accumulate in the body. If metabolism in the liver is disrupted, the quality of Nifedipine’s work will also change.

Undesirable effects of Nifedipine

Like any systemic drug, Nifedipine affects all organ and tissue systems:

1. Effect on the functioning of the heart and blood vessels. At the very beginning of use, the face may periodically become redder. Sometimes tachycardia develops and the patient can feel his heartbeat. Lower blood pressure occurs less frequently and painful sensations, as during an attack of myocardial infarction.
2. Effect on the hematopoietic system. It is extremely rare, but anemia, leukopenia or thrombocytopenia can sometimes occur.
3. Effect on the nervous system and sensory organs. Headache and dizziness may become constant companions during treatment. Impaired sensitivity of the limbs and vision are extremely rare.
4. Effect on the gastrointestinal tract. Constipation, nausea, and diarrhea sometimes complicate the process of taking the drug, but not significantly. In rare cases, the activity of liver enzymes increases, since the transformation of the drug occurs in this organ.
5. Effect on the respiratory system. Almost never occurs, although bronchospasm is sometimes possible.
6. Effect on the kidneys. Patients with renal failure are at risk of increased daily diuresis and deterioration of excretory function.
7. Allergy. Possible in case of high susceptibility to the substances that make up the drug. Manifests itself in the form of itching and urticaria.

It is worth remembering that if there are any side effects of the medication, you should contact a specialist. The therapist or cardiologist will select another remedy with a similar effect, but without undesirable effects.

Watch also the video: When is the right time to take blood pressure pills?

What can you take with Nifedipine?

Drugs such as nitrates, beta blockers, angiotensin II receptor blockers, diuretics, and antidepressants can further lower blood pressure. The use of these drugs is possible only under the supervision of a physician.

Alcohol intake has the same effect on the body, so you should abstain from it during treatment. Aspirin, Omeprazole, antifungal drugs, hypoglycemic agents and immunosuppressants do not affect the effectiveness of Nifedipine and can be taken in the prescribed dosage.

Antiepileptic drugs, the antibiotic Rifampicin, significantly reduce the degree of exposure of the drug to the body. If you use these drugs, it is better to choose another drug that will reduce blood pressure.

Dosage and overdose

The attending physician decides in what dosage the tablets should be taken for each specific patient. He will be able to assess how severe the disease is and whether the response to the therapy is normal. It is not recommended to prescribe a dose on your own.

Treatment is emergency gastric lavage. Activated carbon and drugs are prescribed that will increase blood pressure and lead to heartbeat back to normal. Calcium preparations are antidotes for Nifedipine. They are used in combination with therapy that is already being carried out. 10% calcium chloride is administered intravenously slowly.

How to take the drug if your blood pressure is high?

Each disease has its own application characteristics. Usually the doctor explains them when prescribing the drug, but you also need to figure it out on your own. Such knowledge may be useful in conditions that require emergency care. If Nifedipine is prescribed, the method of administration for different pressure levels is as follows:

1. For hypertension. Long-acting forms are used to treat arterial hypertension. They help avoid sudden relaxation of blood vessels. Most modern method- the use of special “therapeutic systems” that keep the amount of Nifedipine in the bloodstream at the same level all day.
2. At hypertensive crisis The pressure cannot be reduced sharply. First you need to reduce it by about 10-15% from the original numbers. Short-acting forms are used for treatment, and Nifedipine is the drug of first choice. The tablets are placed under the tongue. The effect should occur approximately 10 minutes after application and last until the ambulance arrives.
3. Cardiac ischemia. Stable angina, like hypertension, is treated with long-acting medications. When Nifedipine is prescribed, the patient's need for nitroglycerin is reduced. Short-acting drugs are also used to relieve attacks of angina. The method of their use corresponds to a hypertensive crisis.
4. Pulmonary hypertension. The drug for pulmonary hypertension is prescribed in average therapeutic doses. After starting use, the doctor observes how the patient’s body reacts to taken medication and is there any effect? If necessary, the dose can be increased after 3-5 days. Gradually, a balance is found between the desired effect and tolerability.

Any patient using Nifedipine needs to know its instructions for use and at what pressure levels it can be used. When prescribing, the doctor will tell you how and in what dosage to take. But this does not exclude the patient’s responsibility for his own health.

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Nifedipine: instructions for use and reviews