Comparative Pharmacology
Head-to-head clinical analysis: CARDIZEM LA versus ISOPTIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CARDIZEM LA versus ISOPTIN.
CARDIZEM LA vs ISOPTIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Cardizem LA (diltiazem) is a calcium channel blocker that inhibits calcium ion influx across cardiac and smooth muscle cells during depolarization, leading to negative inotropic, chronotropic, and dromotropic effects. It dilates coronary and peripheral arteries, reducing systemic vascular resistance and myocardial oxygen demand.
Verapamil inhibits calcium ion influx across cardiac and vascular smooth muscle cells, blocking L-type calcium channels, leading to vasodilation and reduced myocardial contractility and conduction velocity.
Oral, 180-360 mg once daily; initiate at 180 mg once daily, titrate to 240 mg, then 300 mg, then 360 mg once daily as needed.
Initial dose: 80-120 mg orally three times daily; sustained-release: 120-240 mg orally once daily. IV: 5-10 mg slow IV push over 2 minutes, may repeat after 15-30 minutes. Maximum daily oral dose: 480 mg.
None Documented
None Documented
Terminal elimination half-life: 5-8 hours after oral administration. For extended-release formulations, the half-life is similar but the prolonged absorption phase results in sustained plasma concentrations.
Terminal elimination half-life: 4.5-12 hours (mean 8 hours); increases with hepatic impairment or cirrhosis
Urine (2-4% unchanged, ~40% as metabolites); bile/feces (major route, ~60% as metabolites).
Renal (70% as metabolites, 3-5% unchanged); biliary/fecal (25%)
Category C
Category C
Calcium Channel Blocker
Calcium Channel Blocker