However, in patients with severe left ventricular dysfunction. Carbamazepine: The concomitant oral administration of verapamil and carbamazepine may potentiate the effects of carbamazepine neurotoxicity. Drug Interactions: Beta-Adrenergic Blockers: The concomitant administration of verapamil with beta-blockers can result in severe adverse effects see Warnings. The structural formula of Verapamil hydrochloride is: Benzeneacetonitrile, 3,4 dimethoxyphenyl ethyl methylamino propyl 3,4 dimethoxy where can i buy verapamil methylethyl monohydrochloride, Verapamil hydrochloride is white or practically white, crystalline powder. Prophylaxis of repetitive paroxysmal supraventricular tachycardia Essential Hypertension Contraindications Verapamil Hydrochloride Tablets are contraindicated in:. The dosage for prophylaxis of PSVT non-digitalized patients ranges from 240-480 mg day in divided. Adverse Reactions Serious adverse reactions are uncommon when Verapamil hydrochloride therapy is initiated with upward dose titration within the recommended single and total daily dose.