Look for Drugs and Conditions

Verapamil

Verapamil

The antihypertensive effect of verapamil, stems from a decrease in peripheral vascular resistance without an increase in heart rate as a reflex response.It has a marked antiarrhythmic effect, particularly in supraventricular arrhythmias.It delays impulse conduction in the A.V. node. Due to Ca-antagonistic effect on the smooth vascular muscles of the coronaries, verapamil enhances myocardial blood flow, even in poststenotic areas,and relieves coronary spasms which contributes to its anti-ischaemic & anti anginal efficacy in all types of coronary artery diseases.

Indications

Chronic coronary insufficiency, angina pectoris, coronary spasms vasospastic angina, angina after M.I, hypertension. Tachycardias such as paroxysmal supraventricular tachycardia, atrial fibrillation/flutter with tachyarrhythmia, premature beats.


Dosage

Adults: Oral: 40-80 mg 3-4 times a day. Max. 480 mg daily. I.V.: 5 mg initially, if desired effect is not achieved, further 5 mg after 5-10 minutes. Children: Oral: Less than 6 years up to 40 mg BD or TID. 6-12 years: 40-120 mg BD or TID. Max. 360 mg/day. I.V.: 1-5 years: 2-3 mg, 6-14 years 2.5-5 mg only at onset.


Contra-Indications

Cardiovascular shock, acute M.I. (bradycardia, hypotension, L.V.F.), severe conduction disorders (2nd & 3rd degree A V block, sinoatrial block) sick sinus syndrome.


Special Precautions

Ability to drive or operate machinery may be impaired. Hepatic or renal impairment. Paediatrics: Reduced dose necessary. Pregnancy: Not recommended. Lactation: Drug passes into the breast milk. But at normal doses adverse effects on the baby are unlikely. Elderly: No special problems.


Side Effects

Constipation,nausea, vertigo or dizziness, headache, flushing, fatigue, nervousness, ankle oedemas, erythromelalgia and paresthesia.


Drug Interactions

Beta-blockers, other antihypertensives, neuromuscular blockers, digitalis, carbamazepine potentiated. Quinidine reduces blood levels & combination may result in profound cardiac depression. Phenobarb, rifampicin, phenytoin increase metabolism. Potentiates neurotoxicity by carbamazepine.


Ad 5