Verapamil hydrochloride (Isoptin; Knoll Pharmaceuticals, Whippany, New Jersey), a papaverine derivative currently being tested experimentally in the United States, is a calcium channel blocking agent used for treatment of angina pectoris (1, 2), supraventricular arrhythmias (3, 4), and subaortic stenosis (5). Reported adverse effects from verapamil include: hypotension (4, 6), negative inotroppy (6), atrioventricular block (7), and mild nausea and constipation (1). We describe a case of verapamil induced hepatotoxicity.
A 55-year-old white man with Class II exertional angina consented to a double-blind serial treadmill exercise test protocol to evaluate the anti-anginal efficacy of verapamil. Prior cardiac catheterization showed a