Verapamil, pills 40mg, 30pcs

Composition

Active ingredient:

40 mg of verapamil.

Pharmacological action

Pharmacodynamics

Verapamil has antianginal, antihypertensive, antiarrhythmic effects.

Blocks calcium channels and lowers the transmembrane calcium current. Reduces contractility, the frequency of the sinus node pacemaker and the speed of conduction in the AV node, sinoatrial and AV conduction, relaxes smooth muscles (more arterioles than veins), causes peripheral vasodilation, lowers total peripheral vascular resistance, reduces afterload.

Increases myocardial perfusion, reduces the disparity between the need and supply of oxygen to the heart, promotes regression of left ventricular hypertrophy, lowers blood pressure. Prevents the development and eliminates spasm of the coronary arteries in case of variant angina pectoris. In patients with uncomplicated hypertrophic cardiomyopathy, it improves the outflow of blood from the ventricles. Reduces the frequency and severity of headaches of vascular origin.

Antiarrhythmic effects develop in 1-5 minutes after intravenous use, hemodynamic effects-within 3-5 minutes.

Pharmacokinetics

When taken orally, it is rapidly absorbed in the small intestine, absorption – 90-92%, bioavailability after a single dose-24-35% due to intensive metabolism during the” first pass ” through the liver and increases 1.5-2 times with prolonged use. With prolonged use in increasing doses, bioavailability may increase.

The time to reach the maximum concentration of the drug in blood plasma is 1-2 hours when taken orally. The maximum concentration of the drug in blood plasma (Cmax) is 80-400 ng/ml. Binding to plasma proteins is 90%. Penetrates through the blood-brain barrier, placental barrier (20-92% concentration in maternal blood plasma) and into breast milk (in low concentrations).

It is rapidly metabolized in the liver by N-dealkylation and O-demethylation, with the formation of several metabolites (12 were identified in humans). Accumulation of the drug and its metabolites in the body explains the increased effect of course treatment. The main pharmacologically active meta-pain is norverapamil (20% of the antihypertensive activity of verapamil). CYP3A4, CYP3A5, and CYP3A7 isoenzymes are involved in drug metabolism.

The half – life of the drug is 3-7 hours with a single dose,4-12 hours – with prolonged use (due to saturation of the liver enzyme systems and increased plasma concentrations, the half-elimination period of the drug increases almost 2 times). With hepatic insufficiency, bioavailability increases and the half-life of the drug increases. 70% is excreted by the kidneys (3-5% unchanged),16-25% – with bile. It is not excreted during hemodialysis.

When administered intravenously, the half-life is biphasic: early-about 4 minutes, final-2-5 hours. It binds to plasma proteins by 90%. It is metabolized in the liver to form norverapamil, which has 20% of the antihypertensive activity of verapamil, and 11 other metabolites (determined in trace amounts).

It is mainly excreted by the kidneys, partially-with feces (16%). Penetrates into breast milk, passes through the placenta. In severe hepatic impairment, plasma clearance decreases by 70%, and the elimination half-life increases to 14-16 hours.

Indications

• Treatment and prevention of CHD: chronic stable angina (tension angina), unstable angina, vasospastic angina (Prinzmetal angina/variant angina).
• Treatment and prevention of cardiac arrhythmias: paroxysmal supraventricular tachycardia, chronic atrial flutter and flicker (tachyarrhythmic variant), supraventricular extrasystole.
• Arterial hypertension. Hypertensive crisis.
• Hypertrophic cardiomyopathy.

Contraindications

• hypersensitivity to verapamil,
• myocardial infarction complicated by bradycardia,
• sick sinus syndrome node,
• cardiogenic shock,
• atrioventricular blockade II and III degree,
• the WPW syndrome,
• severe hypotension or left ventricular failure,
• chronic heart failure of PB-III stages,
• acute heart failure,
• bradycardia less than 50 beats/min,
• hypotension – AD systolic less than 90 mm Hg. St. ;
• simultaneous intravenous use of beta-blockers.

Side effects

From the cardiovascular system:  bradycardia (less than 50 beats/min), marked reduction in blood pressure, the development or the worsening of heart failure, tachycardia; rarely angina, until the development of myocardial infarction (especially in patients with severe obstructive coronary artery disease), arrhythmia (including atrial fibrillation and ventricular); with the rapid on/in the introduction, AV-block III degree, asystole, collapse.

From the central nervous system and peripheral nervous system:  dizziness, headache, fainting, anxiety, lethargy, increased fatigue, asthenia, drowsiness, depression, extrapyramidal disorders (ataxia, masked face, shuffling gait, stiffness of the hands or feet, trembling of the hands and fingers, difficulty swallowing).

From the digestive system:  nausea, constipation (rarely-diarrhea), gum hyperplasia (bleeding, soreness, swelling), increased appetite, increased activity of hepatic transaminases and alkaline phosphatase.

Allergic reactions: pruritus, skin rash, hyperemia of the facial skin, erythema multiforme (including Stevens-Johnson syndrome).

Other services:  weight gain, very rare-agranulocytosis, gynecomastia, hyperprolactinemia, galactorrhea, arthritis, transient vision loss on the background of Cmax, pulmonary edema, asymptomatic thrombocytopenia, peripheral edema.

Interaction

Concomitant use of Verapamil and beta-blockers, antiarrhythmic drugs, and inhaled anesthesia may lead to a mutual increase in their cardiodepressive effects (AV block, bradycardia, hypotension, and heart failure). When used concomitantly with quinidine, patients with hypertrophic obstructive cardiomyopathy may develop severe hypotension and pulmonary edema.

When Verapamil is co-administered with other antihypertensive drugs, there is a mutual potentiation of their effects. Verapamil can significantly increase the concentration of digoxin in plasma, which requires a reduction in the dose of cardiac glycoside when co-administered.

The neurotoxic effect of Verapamil is potentiated by carbamazepine and lithium salts, and the psychotropic effect of lithium when co-administered with verapamil is weakened. The concentration of cyclosporine or theophylline in blood plasma increases when co-administered with Verapamil. Rifampicin, phenytoin, phenobarbital and cimetidine can reduce the concentration of Verapamil in plasma and reduce the effectiveness of the latter. Verapamil potentiates the action of muscle relaxants.

How to take, course of use and dosage

The dosage regimen of Verapamil is set individually.

Adults are prescribed an initial dose of 40-80 mg 3 times a day. The maximum daily dose is 480 mg. Children aged 6-14 years are prescribed 80-360 mg per day, children under 6 years-40-60 mg per day; the frequency of use is 3-4 times a day.

Dragees are taken with a meal or immediately after a meal, washed down with a small amount of water.

Overdose

Symptoms: bradycardia, AV block, marked decrease in blood pressure, heart rate, shock, asystole, SA block.

Treatment: for early detection – gastric lavage, activated charcoal; for rhythm and conduction disorders-intravenous isoprenaline, norepinephrine, atropine,10-20 ml of 10% calcium gluconate solution, artificial pacemaker; intravenous infusion of plasma-substituting solutions.

To increase blood pressure in patients with IGSS, alpha-adrenostimulants (phenylephrine) are prescribed; isoprenaline and norepinephrine should not be used.

Hemodialysis is ineffective.

Special instructions

With caution, the drug is prescribed to patients with impaired liver function, with acute myocardial infarction. The use of Verapamil during pregnancy is possible only if the intended benefit to the mother exceeds the potential risk to the fetus.

When using the drug during lactation, the question of stopping breastfeeding should be decided.

With caution, Verapamil is prescribed to patients engaged in potentially dangerous activities that require increased attention and speed of motor and mental reactions.

Form of production

Tablets

Storage conditions

Store at a temperature not exceeding 25°C.

Shelf life

3 years

Active ingredient

Verapamil

Conditions of release from pharmacies

By prescription

Dosage form

Tablets

Purpose

For adults

Indications

Arrhythmia, Hypertension