Instructions for use NIFEDIPINE

Release forms

There are two main forms of release of Nifedipine - tablets and gel-emulsion. Most often, patients are prescribed tablets. They contain a high content of active substance. Gel emulsion is an auxiliary preparation.

Tablets weighing 10 g can be packaged in blisters of 10 pieces each. These blisters are packed in cardboard boxes. Also, tablets of 20 or 50 pieces can be placed in plastic jars.

The gel emulsion is stored in a tube weighing 40 g. This medicine in this form of release is used only for the treatment of hemorrhoids.

There is also Nifedipine in the form of a solution for intravenous injection, as well as in the form of boluses that are injected into the coronary vessels.

How it affects the body

The medicine is a calcium antagonist and belongs to the group of slow calcium channel blockers (SCBC). The substance slows down the process of calcium penetration into the muscle cells of the heart, as well as into the cells of vascular muscles. Under the influence of the drug, the myocardium consumes less oxygen. Nifedipine lowers blood pressure and total peripheral vascular resistance, and the ability of the myocardium to contract is also slightly reduced.

Thanks to the medicine, the tone of the smooth muscles located in the vessels slightly decreases, therefore the peripheral and coronary arteries dilate. Due to this, blood flow in the coronary vessels is normalized. Myocardial conductivity is not inhibited. But you need to remember that Nifedipine does not act against arrhythmia and does not normalize heart rhythm.

How long does it take for the medicine to work?

Nifedipine has antianginal and antihypertensive effects. Relaxes vascular smooth muscle (relieves spasm), dilates coronary and peripheral (mainly arterial) vessels, reduces blood pressure and peripheral vascular resistance, and reduces afterload. Possessing a cardioprotector effect, it reduces the need for oxygen in the heart muscle. Increases coronary blood flow. Nifedipine effectively reduces blood pressure and also helps relieve muscle spasms. Without affecting the heart rhythm, it significantly lowers blood pressure. After administration, Nifedipine begins to act within 20 minutes. (chewing accelerates the effect) and lasts up to 12 hours.

Active ingredient: tablets and capsules 0.005 and 0.01 g. Dragee 0.01 g. Retard tablets 0.02 and 0.04 g.

For long-term treatment of cardiovascular diseases and arterial hypertension, patients are prescribed long-acting Nifedipine.

It is this dosage form that ensures a slow and measured flow of the component into the human blood, promotes a smooth decrease in blood pressure, reduces the risk of atherosclerosis, tachycardia, headaches and periodic “jumps” in the well-being of the patient being treated. Compared to other cardiac drugs, Nifedipine extended-release has fewer contraindications and side effects, and therefore is applicable to the majority of the population in need of quality treatment.

Indications for use

The doctor prescribes Nifedipine for the treatment of many diseases and pathological conditions:

• angina pectoris, including vasospastic;
• hypertension;
• Raynaud's disease;
• hypertension;
• hypertensive crisis.

Nifedipine is necessary for the prevention and relief of angina attacks, as well as for lowering blood pressure.

The doctor may recommend that the patient take the medicine only once a day. This is due to the fact that Nifedipine is active throughout the day.

For hemorrhoids at any stage up to the 4th stage, the doctor can prescribe Nifedipine gel. This gel dilates blood vessels and normalizes blood flow, which means it will help with rectal bleeding.

Why is the drug prescribed?

Nifedipine not only reduces blood pressure, but also protects the myocardium from lack of oxygen, as well as overloads that occur with high peripheral vascular resistance. The drug reduces the stretching of the heart muscle, enhancing metabolic processes in it. The drug Nifedipine has the following indications for use:

• hypertension syndrome; chronic heart failure;
• angiospathic cerebral circulatory disorders;
• ischemia;
• bradycardia and angina pectoris;
• spasm of blood vessels in the inner ear and retina.

Nifedipine tablets for lowering blood pressure are an effective means of providing emergency assistance during a hypertensive crisis. Extended-release nifedipine in combination with bronchodilators is prescribed as maintenance therapy for bronchial asthma and Raynaud's disease. Efficacy in hypertension The hypotensive effect of Nifedepine is expressed in slowing down the movement of calcium through the membrane of the smooth muscle cells of the arteries.

Calcium ions spasm blood vessels and increase their contraction, and the medicine blocks their flow. It ensures expansion of the lumen of the coronary and peripheral branches of the arterial network, while reducing the resistance of the vascular walls and reducing the load on the heart. The drug is well absorbed into the digestive tract, thereby its effect begins in the first ten minutes after use, which is especially important during a hypertensive crisis.

Instructions for use

The attending physician prescribes an individual dosage to the patient and selects the drug in a suitable release form.

How to take Nifedipine tablets - instructions:

1. At the beginning of the course of treatment, the doctor may prescribe 1 tablet (10 mg) 3-4 times a day.
2. Then it may be necessary to take 2 tablets (20 mg) 3-4 times a day.
3. In severe cases, the dose is increased to 3 tablets (30 mg) 3-4 times a day. This occurs with severe hypertension, as well as with variant angina.
4. In case of an acute attack of angina, it is recommended to take 1-2 tablets (10-20 mg) under the tongue.

An acute attack can be stopped with Nifedipine injections. Within 4–8 hours, injections of 5 mg of the drug are given.

For severe spasms of the coronary arteries, Nifedipine boluses of 100–200 mcg are used. They are injected directly into the vessels (intracoronary). To treat coronary stenosis, boluses of 50–100 mcg are taken.

You must take the medicine strictly in accordance with the recommendations and prescriptions of your doctor. You should not self-medicate, otherwise you can harm your health.

How to take with high blood pressure?

When the medicine is used for long-term treatment of high blood pressure and cardiac ischemia, it is best to give preference to the prolonged form, which lasts for about a day. Fast-acting tablets can be used only in extreme cases, when you urgently need to get rid of the symptoms of a hypertensive crisis. If you constantly take this type of Nifedipine, it can end in a heart attack or stroke. You cannot select the dosage yourself; this is done by a doctor, otherwise everything can end in very disastrous consequences. When prescribing long-acting tablets, you should not take the medicine more than once a day. In addition, the drug does not divide, dissolve or dissolve. Should be taken orally with water. The Nifedipine dosage regimen should be drawn up by a doctor, taking into account the individual characteristics of the body.

The instructions for use of the product do not indicate at what pressure to use it, but the main points of treatment with it are described there.

The tablets are taken orally, without chewing and with plenty of liquid. This can be done regardless of food intake. At the beginning of treatment, 10 mg of the drug is used once a day.

If this dose is ineffective, it can be doubled. In this case, the tablets are taken twice a day with a break of 12 hours. For ischemic disease, more serious dosages may be required. In this case, they are increased, gradually increasing to 60 mg. The course of treatment with Nifedipine is compiled by the doctor individually. In some cases, dose adjustment may be required. You should not stop taking the drug abruptly. Withdrawal syndrome may occur.

Side effects

The medicine may cause some side symptoms. To relieve them, your doctor may prescribe additional medications.

Side effects:

• increased heart rate;
• skin redness;
• feeling of warmth or heat on the skin;
• hypotension;
• slight swelling;
• skin rash;
• ventricular tachycardia;
• slow heart rate;
• increased attacks of angina pectoris;
• cardiac arrest, asystole;
• heartburn, nausea, diarrhea;
• swelling of the gums;
• liver dysfunction;
• muscle pain;
• headache;
• sleep disorders;
• tremor of the limbs;
• visual disturbances;
• thrombocytopenia;
• leukopenia;
• renal dysfunction;
• increase in the daily amount of urine excreted;
• sudden enlargement of the breast (gynecomastia).

After an intravenous injection, the patient may feel a burning sensation. After intracoronary administration of the drug, within the first minute the patient’s pulse may sharply increase and blood pressure may drop. These unpleasant sensations disappear after 5–15 minutes.

Contraindications

There are many contraindications that prohibit the use of this drug for some patients:

• collapse;
• severe form of heart failure;
• hypotension, in which systolic (upper) pressure falls below 90 mmHg;
• cardiogenic shock;
• the first 4 weeks after myocardial infarction (acute period);
• aortic stenosis;
• unstable form of angina;
• lactose intolerance, lactase deficiency;
• GGM syndrome - impaired absorption of glucose and galactose;
• increased individual intolerance;
• lactation period;
• pregnancy less than 20 weeks;
• children's age (up to 18 years).

For these diagnoses and conditions, it is necessary to prescribe other medications to the patient. Nifedipine is not suitable for long-term treatment.

Recently, cardiologists conducted a study in which they proved that Nifedipine increases the risk of sudden cardiac arrest, so this medicine must be taken with extreme caution.

Instructions for use NIFEDIPINE

The drug is prescribed with caution for very low blood pressure (severe hypotension with systolic blood pressure below 90 mm Hg), as well as for severe cardiac weakness (decompensated heart failure).

In case of severe arterial hypotension (systolic pressure below 90 mm Hg), severe cerebrovascular accidents, severe heart failure, severe aortic stenosis, diabetes mellitus, impaired liver and kidney function, Nifedipine can be used only under conditions of constant clinical monitoring, avoiding the appointment of high doses of the drug.

In elderly patients (over 60 years of age), the drug is dosed with great caution.

Features of application.

Nifedipine should be prescribed with particular caution to patients undergoing hemodialysis, as well as patients with malignant hypotension or hypovolemia (decreased blood volume), since dilation of blood vessels can cause a significant decrease in blood pressure in them.

Some in vitro experiments have revealed a relationship between the use of calcium antagonists, in particular nifedipine, and reverse biochemical changes in sperm that impair the latter’s ability to fertilize. When treating coronary vasospasm in the post-infarction period, treatment with Nifedipine should begin approximately 3-4 weeks after myocardial infarction and only if the coronary circulation is stabilized.

Grapefruit juice inhibits the metabolism of nifedipine, which causes an increase in the concentration of the latter in the blood plasma and potentiation of the hypotensive effect of the drug. The use of nifedipine may lead to falsely elevated results when spectrophotometrically determining the concentration of vanillin-mideic acid in urine (however, this effect is not observed when using the high-performance liquid chromatography method).

Use during pregnancy or breastfeeding.

Nifedipine passes into breast milk, so breastfeeding should be discontinued if the use of Nifedipine is necessary during lactation.

Children.

The drug is not used in children under 14 years of age.

The ability to influence the reaction rate when driving a vehicle or working with other mechanisms.

When using the drug, driving vehicles and working with other potentially dangerous mechanisms is not recommended.

Carefully

Patients suffering from certain diseases should be extremely attentive to their health. They will have to drink Nifedipine with caution:

• elderly patients;
• hypertrophic obstructive cardiomyopathy;
• severe liver diseases;
• sick sinus syndrome;
• kidney dysfunction;
• mitral valve stenosis;
• chronic heart failure;
• diabetes;
• stenosis of any part of the intestine;
• disturbances in the functioning of cerebral vessels.

Taking the medication in these cases should be strictly under the control and supervision of the attending physician.

Overdose symptoms

You should not take more than 120 mg tablets per day. The maximum dose of intravenous solution is 30 mg.

Signs of overdose:

• a sharp slowdown in heart rate;
• bradyarrhythmia;
• heart rhythm disturbances;
• hypotension;
• collapse;
• cardiogenic shock;
• convulsions;
• loss of consciousness;
• hypoxia;
• acidosis;
• slowing of cardiac conduction;
• hyperglycemia;
• coma.

Symptoms appear 3-4 hours after taking the tablets. In case of overdose, the patient's stomach is washed and activated charcoal is administered. He is then given intravenous injections of atropine with calcium gluconate, calcium chloride and norepinephrine to relieve intoxication. Due to proven ineffectiveness, hemodialysis is not performed.

Interaction with other drugs

Blood pressure drops sharply when Nifedipine is taken simultaneously with other antihypertensive drugs, as well as diuretics, diltiazem, and drugs based on phenothiazine and its derivatives.

Attention and memory may be affected when Nifedipine is used with anticholinergic medications.

This medicine should not be combined with beta-blockers, otherwise severe hypotension and even heart failure may occur.

In combination with magnesium salts, the patient experiences severe muscle weakness.

The effective effect against angina pectoris is enhanced when the drug is combined with nitrates.

Due to the intake of digoxin and theophylline, the amount of these substances in the blood increases.

You should not take Nifedipine together with medications containing calcium. These substances have opposite properties, which reduces their effectiveness. Side effects of the drug are enhanced in combination with fluoxetine and vincristine. Also, the effect of Nifedipine is reduced in combination with rifampicin, so these two drugs are incompatible with each other.

The level of nifedipine in the blood decreases if you take the medicine together with phenytoin, phenobarbital or carbamazepine. Conversely, concentrations increase in combination with itraconazole, cimetidine, fluconazole and ranitidine.

The QT interval on the ECG is prolonged when Nifedipine is taken simultaneously with quinidine. This occurs because the amount of quinidine in the blood decreases sharply, and when it is discontinued, it suddenly increases.

Severe hypotension, dizziness and other unpleasant symptoms occur if the patient drinks Nifedipine and drinks containing ethyl alcohol. This drug should not be combined with grapefruit juice.

Nifedipine

Medicines that affect nifedipine

Nifedipine is metabolized with the participation of the CYP3A4 isoenzyme of the cytochrome P450 system, located in the intestinal mucosa and in the liver.

Drugs that inhibit or induce this enzyme system may affect the first-pass effect (after oral administration) or clearance of nifedipine (see section Special instructions

).

The strength of the interaction and the duration of this effect should be taken into account when taking nifedipine simultaneously with the following drugs

Rifampicin

Rifampicin greatly increases the activity of the CYP3A4 isoenzyme of the cytochrome P450 system, which leads to a significant decrease in the bioavailability and effectiveness of nifedipine, therefore their simultaneous use is contraindicated (see section Contraindications

).

During simultaneous use of nifedipine with the following weak or moderate inhibitors of the CYP3A4 isoenzyme, blood pressure should be monitored and, if necessary, the dose of Nifedipine should be adjusted (see section Dosage and Administration).

.

Macrolides (eg, erythromycin)

No interaction studies have been conducted between nifedipine and macrolides. It is known that some macrolides can inhibit the CYP3A4 isoenzyme, which is involved in the metabolism of other drugs. Therefore, a potential increase in the concentration of nifedipine in the blood plasma cannot be excluded when taken simultaneously (see section Special instructions

).

Azithromycin does not inhibit the CYP3A4 isoenzyme, although its structure is a macrolide antibiotic.

HIV protease inhibitors (eg, ritonavir, indinavir, nelfinavir, amprenavir)

Clinical studies of the interaction between nifedipine and HIV protease inhibitors are not presented. It is known that drugs of this class inhibit the CYP3A4 isoenzyme. This class of drugs has also been shown to inhibit the CYP3A4 isoenzyme in vitro,

determining the metabolism of nifedipine.
When taken simultaneously with nifedipine, a significant increase in its concentration in the blood plasma cannot be ruled out due to a decrease in the “first pass” effect and a decrease in its elimination (see section Special instructions
).

Azole antifungals (eg, ketoconazole, fluconazole, itraconazole)

Clinical studies of the interaction between nifedipine and azole antifungals have not yet been presented. It is known that drugs of this class inhibit the CYP3A4 isoenzyme. When taken orally with nifedipine simultaneously, a significant increase in its systemic bioavailability cannot be ruled out due to a decrease in the “first pass” effect (see section Special instructions

).

Fluoxetine

Clinical studies of the interaction between nifedipine and fluoxetine are not presented. Fluoxetine is known to inhibit in vitro

isoenzyme CYP3A4, which determines the metabolism of nifedipine. Therefore, an increase in the concentration of nifedipine in the blood plasma cannot be excluded when taken simultaneously (see section Special instructions).

Nefazodone

Clinical studies of the interaction between nifedipine and nefazodone have not yet been reported. It is known that nefazodone inhibits the CYP3A4 isoenzyme, which determines the metabolism of nifedipine. Therefore, an increase in the concentration of nifedipine in the blood plasma cannot be excluded when taken simultaneously (see section Special instructions

).

Quinupristin/Dalfopristin

Concomitant use of quinupristin/dalfopristin with nifedipine may lead to an increase in the concentration of nifedipine in the blood plasma (see section Special instructions

).

Valproic acid

Clinical studies of the potential interaction between nifedipine and valproic acid are not presented. Since it has been established that valproic acid can increase the concentration of a structurally similar BMCA, nimodipine, in the blood plasma, an increase in the concentration of nifedipine in the blood plasma cannot be excluded and, as a result, an increase in its therapeutic effect (see section Special instructions

I).

Cimetidine

Due to the inhibition of the CYP3A4 isoenzyme, cimetidine increases the concentration of nifedipine in the blood plasma and may enhance the antihypertensive effect (see section Special instructions

).

Other types of interaction

Cisapride

Concomitant use of cisapride and nifedipine may lead to an increase in the concentration of nifedipine in the blood plasma.

Inducers of the cytochrome P450 isoenzyme CYP3A4, including antiepileptic drugs such as phenytoin, carbamazette and phenobarbital

Phenytoin induces the CYP3A4 isoenzyme. With simultaneous use of nifedipine with phenytoin, the bioavailability of nifedipine is reduced and, thus, its effectiveness is reduced. When taking these drugs simultaneously, the clinical effect of nifedipine should be assessed and, if necessary, it is recommended to increase its dose. If the dose of nifedipine is increased during concomitant use of both drugs, a reduction in the dose of nifedipine is required after discontinuation of phenytoin. Clinical studies of the potential interaction between nifedipine and carbamazepine or phenobarbital are not presented. Since it was found that, due to enzyme induction, both drugs can reduce the concentration of BMCC, nimodipine, which is similar in structure, in the blood plasma, a decrease in the concentration of nifedipine in the blood plasma and, as a result, a decrease in its therapeutic effect cannot be ruled out.

Effect of nifedipine on other drugs:

Drugs that lower blood pressure

The combined use of nifedipine with other antihypertensive drugs can lead to a mutual enhancement of the antihypertensive effect, such drugs, for example, include:

• Diuretics,
• Beta blockers,
• Angiotensin-converting enzyme inhibitors,
• Angiotensin I receptor antagonists,
• BMKK,
• Alpha blockers,
• Phosphodiesterase type 5 inhibitors,
• Methyldopa,
• Magnesium sulfate.

When using nifedipine and beta-blockers simultaneously, patients should be closely monitored, as in some cases the course of chronic heart failure may worsen.

Digoxin

The simultaneous use of nifedipine and digoxin may lead to a decrease in the clearance of digoxin and, as a result, to an increase in its concentration in the blood plasma. The patient should be carefully monitored for symptoms of digoxin overdose and, if necessary, reduce the dose of digoxin, taking into account its plasma concentration.

Quinidine

When combined with quinidine, its plasma concentration may decrease in some patients, and subsequently, when nifedipine is stopped, it may increase significantly. Therefore, when taking nifedipine concomitantly or discontinuing it after co-administration with quinidine, it is recommended to carefully monitor the concentration of quinidine in the blood plasma and, if necessary, adjust its dose. An increase in the concentration of nifedipine in the blood plasma has also been reported during the simultaneous use of drugs, while at the same time, in some patients there is no change in the pharmacokinetic parameters of nifedipine. When adding quinidine to nifedipine therapy, blood pressure should be monitored and, if necessary, it is recommended to reduce the dose of nifedipine.

Tacrolimus

Tacrolimus is metabolized by the cytochrome P450 isoenzyme CYP3A4. Recently published data indicate that the dose of tacrolimus when coadministered with nifedipine may be reduced in some patients. When taking drugs simultaneously, the concentration of tacrolimus in the blood plasma should be monitored, and if necessary, it is recommended to reduce its dose.

Grapefruit juice

Grapefruit juice inhibits the CYP3A4 isoenzyme of the cytochrome P450 system. Taking nifedipine with grapefruit juice may lead to increased plasma concentrations of nifedipine and prolongation of its action as a result of reduced first-pass metabolism or decreased clearance. This may lead to an increase in the antihypertensive effect of nifedipine. If you take grapefruit juice regularly, this effect can last at least 3 days after your last intake. Grapefruit juice should be avoided while taking nifedipine (see Dosage and Administration).

).

Other forms of interaction
Nifedipine may cause a false increase in the concentration of vanillylmandelic acid in urine when determined by the spectrophotometric method, but does not affect the results of measurements using the high-performance liquid chromatography (HPLC) method.

special instructions

Nifedipine should be taken only under the strict supervision of doctors. Elderly patients are advised to reduce the dose. The medicine causes withdrawal symptoms, so it is discontinued gradually. It is necessary to discontinue the drug if the patient experiences chest pain.

If a person has stenosis of two coronary vessels, then the medicine cannot be administered intracoronarily into the third.

During the course of treatment it is forbidden to drink alcohol. It is advisable to refrain from working with machinery, driving a car or other types of transport, and also avoid dangerous work that requires great concentration.

Analogs

The following drugs are complete or partial analogues of Nifedipine:

1. "Calcigard Retard".
2. "Cordaflex".
3. "Cordipin Retard."
4. "Kordipin HL".
5. "Corinfar".
6. "Corinfar Retard".
7. "Nifecard HL".
8. "Phenigidine."

The doctor may prescribe these drugs instead of Nifedipine. They have similar properties.

Nifedipine: analogues and substitutes

Cordaflex (Hungary)
. The drug is in the pharmacotherapeutic “top” of the list of Nifedipine analogues. It has a hypotensive and at the same time anti-ischemic effect. Due to the decrease in calcium ions, the reserve force of the myocardium increases. Stabilizes mood. Eliminates high intensity headaches. The therapeutic effect appears twenty minutes after administration. Included in the standards of medical care for the treatment of: Coronary heart disease. Prinzmetal's angina.

Table 30 mg No. 20 - 90 rubles, 60 mg - 126 rubles.

Corinfar (Israel)

. Analogue of Nifedipine in action and structural substance. Activates the removal of sodium ions from the body. Saturates the heart muscle with oxygen. Stimulates blood flow in the myocardium. Improves blood supply to damaged (ischemic) areas of the heart muscle without developing a “steal effect”. Shows good performance at low systolic pressure levels.

Tab. 10 mg 50 pcs. — 78 rubles, 100 pcs. — 130 rub.

Nifecard HL (Switzerland)

.
Improves the transmembrane current of calcium ions disturbed as a result of arterial hypertension. Normalizes cerebral and capillary blood circulation. Reduces:

• Peripheral vascular resistance.
• Load on the heart.
• It affects arterial vessels by expanding them. Appointed:
• With high blood pressure levels.
• Coronary heart disease.
• To relieve attacks of angina pectoris.

Tablets 30 mg No. 20 - 190 rubles, 60 mg - 300 rubles.