Comparative Pharmacology
Head-to-head clinical analysis: CARDIZEM CD versus VERELAN PM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CARDIZEM CD versus VERELAN PM.
CARDIZEM CD vs VERELAN PM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Diltiazem is a calcium channel blocker that inhibits calcium ion influx across cardiac and vascular smooth muscle cell membranes, resulting in dilation of coronary arteries and peripheral arterioles, and decreased myocardial contractility and conduction velocity.
Verapamil is a calcium channel blocker that inhibits the influx of calcium ions across the cardiac and vascular smooth muscle cells, thereby reducing myocardial contractility, sinoatrial and atrioventricular node conduction, and vascular tone.
Hypertension: 180-360 mg once daily orally. Angina: 120-360 mg once daily orally. Maximum dose: 480 mg/day.
Verelan PM (verapamil hydrochloride) is an extended-release oral capsule administered once daily at bedtime. Typical adult dose for hypertension is 200 mg to 400 mg once daily at bedtime. Initial dose is 200 mg, titrated upward as needed. Maximum recommended dose is 400 mg daily.
None Documented
None Documented
Terminal elimination half-life: 6-8 hours (single dose), prolonged to 10-15 hours with multiple dosing or in elderly/hepatic impairment. Clinical context: Therapeutic steady-state achieved in 2-4 days.
Terminal elimination half-life 7.2 ± 1.5 hours after oral administration, prolonged in hepatic impairment (up to 14-16 hours) and elderly; steady-state achieved after 3-4 days.
Renal: ~2-4% (unchanged), Hepatic metabolism to multiple metabolites; ~65% renal (metabolites), ~35% fecal/biliary. Total clearance: 5-7 mL/kg/min.
Primarily hepatic metabolism (>95%), with 3-4% excreted unchanged in urine; biliary/fecal excretion accounts for <1% of unchanged drug.
Category C
Category C
Calcium Channel Blocker
Calcium Channel Blocker