Diltiazem
Diltiazem is a benzothiazepine derivative with antihypertensive and vasodilating properties. Approved in 1982 by the FDA, it is a member of the non-dihydropyridine calcium channel blockers drug class. It works through various mechanisms of action, but it primarily works by inhibiting the calcium influx into cardiac and vascular smooth muscle during depolarization. Compared to dihydropyridine drugs, such as [nifedipine], that preferentially act on vascular smooth muscle and [verapamil] that directly acts on the heart muscle, diltiazem displays an intermediate specificity to target both the cardiac and vascular smooth muscle. Being a potent vasodilator, diltiazem is used clinically as an antihypertensive, anti-arrhythmic, and as an anti-anginal agent for the management of cardiovascular conditions such as hypertension, chronic stable angina, atrial fibrillation, atrial flutter. Apart from its main FDA-approved indications, diltiazem has also been used for numerous off-label indications, such as anal fissures (in topical formulations), migraine prophylaxis, pulmonary hypertension, and rest-related cramps in the lower extremities. Typically available in extended-release oral and intravenous formulations, diltiazem is marketed under various brand names with Cardizem and Tiazac being the most common ones.