Comparative Pharmacology
Head-to-head clinical analysis: CALAN versus ISOPTIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CALAN versus ISOPTIN.
CALAN vs ISOPTIN
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.
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.
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.
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 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: 4.5-12 hours (mean 8 hours); increases with hepatic impairment or cirrhosis
Approximately 70% renal (3-4% unchanged, remainder as metabolites) and 25% biliary/fecal.
Renal (70% as metabolites, 3-5% unchanged); biliary/fecal (25%)
Category C
Category C
Calcium Channel Blocker
Calcium Channel Blocker