Drug class
CARDIZEM CD (diltiazem hydrochloride) is a "calcium ion cellular influx inhibitor (slow channel blocker or calcium antagonist)" that inhibits calcium influx during membrane depolarization of cardiac and vascular smooth muscle, producing coronary and peripheral vasodilation and slowing cardiac conduction.
Uses
Diltiazem hydrochloride extended-release capsules are indicated for: - "Treatment of hypertension," alone or in combination with other antihypertensive medications - "Management of chronic stable angina" and "angina due to coronary artery spasm (vasospastic angina)"
Warnings
No boxed warning. Diltiazem is contraindicated in patients with "sick sinus syndrome except in the presence of a functioning ventricular pacemaker," "second- or third-degree AV block" (without a pacemaker), "hypotension (less than 90 mm Hg systolic)," and acute myocardial infarction with pulmonary congestion documented by X-ray. Key warnings cover cardiac conduction abnormalities, including "second- or third-degree AV block" reported in a small percentage of patients, potential worsening of congestive heart failure in patients with ventricular dysfunction, and symptomatic hypotension.
Side effects
In placebo-controlled trials, the most frequently reported adverse reactions were "headache" (5.4%), "bradycardia" (3.3%), "first-degree AV block" (3.3%), "dizziness" (3.0%), and "edema" (2.6%). Other reported effects include flushing, nausea, and asthenia; rare but serious events reported in postmarketing experience include AV block and allergic skin reactions.
