The drug Verapamil Hydrochloride is a calcium ion influx inhibitor also known as a slow-channel blocker or calcium ion antagonist. It exerts its pharmacologic effects by modulating the influx of ionic calcium across the cell membrane of the arterial smooth muscle and in conductive and contractile myocardial cells. This drug comes as almost white, crystalline powder, practically free of odour and bitter taste. This drug is soluble in water, chloroform, and methanol. The active ingredient in the medicine is Verapamil Hydrochloride, and the inactive ingredients are microcrystalline cellulose, iron oxide colorant, lactose, magnesium stearate, corn starch, gelatin, hydroxypropyl cellulose, hypromellose, polyethylene glycol, talc, and titanium dioxide.
Healthcare professionals use Verapamil to treat patients with mild/moderate hypertension and renal hypertension, angina pectoris, and prophylaxis of paroxysmal supraventricular tachycardia and reduce the ventricular rate in atrial fibrillation/flutter.
Dosage and Administration
Verapamil tablets come in the standard strengths of 40 mg, 80 mg, and 120 mg to administer orally. Individualize the dose of Verapamil by titration. One should not exceed the daily dosage of Verapamil Hydrochloride 480 mg/day. As the half-life of Verapamil increases while chronic dosing, the maximum response may be delayed.
Angina: Dosage
Healthcare professionals recommend that the usual dose is 80 mg to 120 mg three times a day. However, there might be a warranty of 40 mg three times a day in patients who may have an increased response to Verapamil. The upward titration should be based on therapeutic efficacy and safety evaluated approximately 8 hours after dosing. Dosage of Verapamil may be increased at daily or weekly intervals until obtaining an optimum clinical response.
Arrhythmias: Dosage
In digitalized patients, the dosage with chronic atrial fibrillation ranges from 240 to 320 mg per day in divided dosages. The dose of Verapamil for the prevention of PSVT ranges from 240 to 480 mg per day in divided doses. Usually, maximum effects for any dosage given will be apparent during the first 48 hours of therapy.
Essential Hypertension
One should individualize the dose by titration. The usual initial monotherapy dose was 80 mg three times a day in clinical trials. One should consider beginning titration at 40 mg three times every day in patients who may respond to lower doses, such as the elderly. The antihypertensive effects of Verapamil are evident within the first week of therapy. The upward titration should be based on therapeutic efficacy, assessed at the end of the dosing interval.
Common Adverse Reactions
The common adverse reactions of Verapamil tablets are:
Constipation
Dizziness
Nausea
Hypotension
Headache
Edema
Fatigue, etc.
Warnings and Precautions
In a clinical experience with 4,954 patients, 87 developed congestive heart failure/pulmonary edema. Avoid Verapamil in patients with severe left ventricular dysfunction or moderate to severe cardiac failure symptoms and in patients who have any degree of ventricular dysfunction in case of beta-adrenergic blocker administration.
The pharmacologic action of Verapamil might produce a decrease in blood pressure below normal levels, which might result in dizziness or symptomatic hypotension. The cases of hypotension observed in 4,954 patients were 2.5% enrolled in clinical trials.
There are reports of hepatocellular injury while administering Verapamil 80 mg, 40 mg or 120 mg. Healthcare professionals recommend periodically monitoring the liver functioning in patients receiving this medicine.
Some patients with paroxysmal(chronic atrial fibrillation or atrial flutter) and a coexisting accessory AV pathway have developed increased antegrade conduction across the path, bypassing the AV node and producing a very rapid ventricular response ventricular fibrillation after receiving intravenous Verapamil.
There are reports of many serious adverse effects in 120 patients with hypertrophic cardiomyopathy who received therapy with the medicine Verapamil at doses up to 720 mg per day.
Since the liver highly metabolizes Verapamil, it should be administered cautiously to patients with impaired hepatic function.
There are reports about Verapamil decreasing neuromuscular transmission in Duchenne’s muscular dystrophy patients and that Verapamil delays recovery from the neuromuscular blocking agent vecuronium.
Excretion of 70% of an administered dose of Verapamil is in the form of metabolites in the urine. One cannot remove Verapamil by hemodialysis. Administer Verapamil generic medicine cautiously to patients with impaired renal function, and monitor such patients carefully for abnormal delay of the PR interval or other signs of overdose.
Cost of Verapamil in India
The Verapamil cost is reasonable in India. You can purchase this medicine from certified pharmaceutical suppliers. Ikris Pharma Network is one of the licensed generic medicine suppliers, supplying for more than 7 years across the globe.