Comparative Pharmacology
Head-to-head clinical analysis: CALAN SR versus CARDIZEM SR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CALAN SR versus CARDIZEM SR.
CALAN SR vs CARDIZEM SR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Verapamil inhibits calcium ion influx across cardiac and vascular smooth muscle cells, blocking L-type calcium channels, leading to negative inotropic, chronotropic, and dromotropic effects, and vasodilation.
Diltiazem inhibits calcium ion influx across cardiac and vascular smooth muscle cell membranes during depolarization, leading to negative inotropic, chronotropic, and dromotropic effects, and vasodilation.
Oral: 180–240 mg once daily; maximum 480 mg/day.
Oral: Initial dose 60-120 mg twice daily; titrate to maximum 360 mg/day divided into two doses.
None Documented
None Documented
Terminal elimination half-life is 6-12 hours (average ~8 hours) after single oral dose; may increase to 12-16 hours with chronic dosing due to saturable hepatic metabolism; clinical context: requires dosing adjustments in hepatic impairment.
3.0-4.5 hours for diltiazem; metabolites (e.g., desacetyldiltiazem) up to 10 hours. Clinical context: dosing interval adjustment in hepatic impairment.
Approximately 70% of the dose is excreted as metabolites in the urine; 3-4% as unchanged drug; 25% eliminated in feces via biliary excretion.
Renal: 2-4% unchanged; hepatic metabolism: ~60-70% (including active metabolites); fecal: ~30-40%.
Category C
Category C
Calcium Channel Blocker
Calcium Channel Blocker