Comparative Pharmacology
Head-to-head clinical analysis: CARDIZEM LA versus CARDIZEM SR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CARDIZEM LA versus CARDIZEM SR.
CARDIZEM LA vs CARDIZEM SR
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.
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, 180-360 mg once daily; initiate at 180 mg once daily, titrate to 240 mg, then 300 mg, then 360 mg once daily as needed.
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: 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.
3.0-4.5 hours for diltiazem; metabolites (e.g., desacetyldiltiazem) up to 10 hours. Clinical context: dosing interval adjustment in hepatic impairment.
Urine (2-4% unchanged, ~40% as metabolites); bile/feces (major route, ~60% as metabolites).
Renal: 2-4% unchanged; hepatic metabolism: ~60-70% (including active metabolites); fecal: ~30-40%.
Category C
Category C
Calcium Channel Blocker
Calcium Channel Blocker