Comparative Pharmacology
Head-to-head clinical analysis: CALAN versus CARDIZEM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CALAN versus CARDIZEM.
CALAN vs CARDIZEM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Verapamil inhibits calcium ion influx through voltage-gated L-type calcium channels in cardiac and vascular smooth muscle, leading to decreased myocardial contractility, slowed AV conduction, and vasodilation.
Diltiazem inhibits calcium influx into cardiac and vascular smooth muscle cells during depolarization by binding to L-type calcium channels. This results in coronary vasodilation, decreased myocardial oxygen demand, and negative chronotropic and inotropic effects.
Initial: 80-120 mg orally 3 times daily; maintenance: 240-480 mg/day in 3-4 divided doses. IV: 5-10 mg over 2 minutes, may repeat after 15-30 minutes.
Oral: 30-120 mg three to four times daily; extended-release: 120-360 mg once daily. IV: Initial 0.25 mg/kg (max 25 mg) bolus over 2 minutes, may repeat in 15 minutes (0.35 mg/kg); maintenance: 5-15 mg/hour continuous infusion.
None Documented
None Documented
Terminal elimination half-life is 3-7 hours for immediate-release; can be prolonged to 12-16 hours with sustained-release due to slow absorption; increased in hepatic impairment.
Terminal elimination half-life is 3.0-4.5 hours in healthy adults; may be prolonged to 7-9 hours in elderly, hepatic impairment, or renal impairment; clinically relevant for dosing frequency.
Approximately 70% renal (3-4% unchanged, remainder as metabolites) and 25% biliary/fecal.
Primarily hepatic metabolism with extensive first-pass effect; approximately 2-4% excreted unchanged in urine; fecal excretion accounts for about 65% of dose as metabolites; renal excretion accounts for about 35% of dose as metabolites.
Category C
Category C
Calcium Channel Blocker
Calcium Channel Blocker