Nifedipine,10 mg 50 pcs

Nifedipine is a selective “slow calcium channel blocker” derivative of 1,4-dihydropyridine. It has antianginal and antihypertensive effects. It reduces the flow of extracellular calcium ions inside cardiomyocytes and smooth muscle cells of coronary and peripheral arteries.

Limits spasm and dilates coronary and peripheral (mainly arterial) vessels, reduces blood pressure, total peripheral vascular resistance, reduces post-load and myocardial oxygen demand. Increases coronary blood flow. Negative chrono-, dromo- and inotropic effects are overridden by reflex activation of the sympathoadrenal system in response to peripheral vasodilatation. It enhances renal blood flow, causes moderate natriuresis. Time of onset of clinical effect is 20 min, duration of clinical effect is 4-6 h.

Pharmacokinetics

Nifedipine is rapidly and almost completely (over 90%) absorbed from the gastrointestinal tract. After oral administration its bioavailability is 40-60%. Food intake increases the bioavailability. It has a “first pass” effect through the liver.

The maximum concentration in plasma is observed after 1-3 hours and is 65 ng/ml. It penetrates through the blood-brain barrier and the placental barrier, is excreted with breast milk. Binding with blood plasma proteins is 90%. It is completely metabolized in the liver.

It is excreted by kidneys as inactive metabolites (70-80% of the dose taken). The elimination half-life is 2-4 hours. There is no cumulative effect. Chronic renal failure, hemodialysis and peritoneal dialysis have no effect on pharmacokinetics. Tolerance to the drug action develops during long-term use (for 2-3 months).

Indications

Ischemic heart disease – angina pectoris at rest and tension (including variant); arterial hypertension (as monotherapy or in combination with other antihypertensive drugs).

Active ingredient

Composition

Active ingredients:

nifedipine – 10 mg;

Auxiliary substances:

Magnesium stearate,

microcrystalline cellulose,

lactose monohydrate,

Potato starch,

Colloidal silica (aerosil),

povidone (polyvinylpyrrolidone low molecular weight medical).

How to take, the dosage

The dosage and course of treatment is determined by the attending physician in each case individually. The initial dose of Nifedipine is 1 pc (10 mg) 2 times a day. If necessary, the dose can be increased to 2 units (20 mg) 4 times a day. The maximum daily dose is 80 mg.

Interaction

The severity of blood pressure decrease is increased when nifedgeshne is concomitantly administered with other hypotensive drugs, cimetidine, ranitidine, diuretics and tricyclic antidepressants.

In combination with nitrates, tachycardia and hypotensive effect of nifedish.

The concomitant administration of beta-adrenoblockers should be done under close medical supervision, as this may cause an overly pronounced decrease in BP, and in some cases may worsen the symptoms of heart failure.

Nifedipine decreases the plasma concentration of quinidine. Increases plasma concentrations of digoxin and theophylline, therefore, the clinical effect and/or plasma levels of digoxin and theophylline should be monitored.

Rifampicin attenuates the effect of nifedipine (accelerates the metabolism of the latter due to induction of liver enzyme activity).

Special Instructions

During treatment it is necessary to refrain from potentially hazardous activities requiring increased concentration and rapid psychomotor reactions, and from the use of ethanol.

The drug is withdrawn gradually (risk of withdrawal syndrome).

Contraindications

Take with caution in patients:
with chronic heart failure, marked liver and/or renal dysfunction; severe cerebral circulation disorders, diabetes mellitus, malignant arterial hypertension, patients on hemodialysis (because of the risk of arterial hypotension).

Side effects

Cardiovascular system disorders: facial hyperemia, fever, tachycardia, peripheral edema (ankles, feet, shins), excessive reduction of blood pressure (BP), syncope, heart failure, in some patients, especially at the beginning of treatment, angina attacks may occur, which requires drug withdrawal.

Nervous system disorders: headache, dizziness, increased fatigue, somnolence. When prolonged oral administration in high doses – limb paresthesia and tremor.

Gastrointestinal tract, liver: dyspeptic disorders (nausea, diarrhea or constipation), with prolonged use – liver dysfunction (intrahepatic cholestasis, increased activity of “liver” transaminases).

Motor system disorders: arthritis and myalgia.

Allergic reactions: skin itching, urticaria, exanthema, autoimmune hepatitis.

Hematopoietic disorders: anemia, leukopenia, thrombocytopenia, thrombocytopenic purpura.

Urinary system disorders: increased daily diuresis, impaired renal function (in patients with renal failure).

Others: “flushes” of blood to the skin of the face, changes in visual perception, gynecomastia (in elderly patients, completely disappearing after cancellation), hyperglycemia, gum hyperplasia.

Overdose

Symptoms: headache, facial hyperemia, decreased BP, sinus node suppression, bradycardia, arrhythmia.

Treatment: gastric lavage with administration of activated charcoal, symptomatic therapy aimed at stabilization of cardiovascular system activity. Calcium is the antidote; slow intravenous injection of 10% calcium chloride or calcium gluconate is indicated, followed by switching to prolonged infusion.

In case of a marked decrease in blood pressure, intravenous dopamine or dobutamine is indicated. In conduction disorders, administration of atropine, isoprenaline or installation of an artificial pacemaker is indicated.

In case of development of heart failure – intravenous strophantine. Catecholamines should be used only in life-threatening circulatory insufficiency (due to their reduced effectiveness, a high dosage is required, which increases the risk of increasing the propensity to arrhythmia due to intoxication). Monitoring of blood glucose and electrolytes (potassium and calcium ions) is recommended, since insulin release is impaired.

Hemodialysis is ineffective.

Similarities