Comparative Pharmacology
Head-to-head clinical analysis: CARDIZEM versus TIAZAC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CARDIZEM versus TIAZAC.
CARDIZEM vs TIAZAC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Diltiazem, a benzothiazepine calcium channel blocker, inhibits calcium ion influx across cardiac and vascular smooth muscle cell membranes, resulting in coronary vasodilation, peripheral vasodilation, decreased myocardial contractility, and decreased AV nodal conduction velocity.
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.
Oral: 120-360 mg once daily; maximum 540 mg daily.
None Documented
None Documented
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.
Terminal elimination half-life is 5-7 hours for immediate-release; for TIAZAC (extended-release), effective half-life is approximately 6-9 hours due to prolonged absorption
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.
Renal (2-4% unchanged, 60% as inactive metabolites); Fecal (30%); Biliary (minor)
Category C
Category C
Calcium Channel Blocker
Calcium Channel Blocker