Comparative Pharmacology
Head-to-head clinical analysis: TARKA versus TIAZAC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: TARKA versus TIAZAC.
TARKA vs TIAZAC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination of trandolapril (angiotensin-converting enzyme inhibitor) and verapamil (calcium channel blocker). Trandolapril inhibits ACE, reducing angiotensin II production, leading to vasodilation and decreased aldosterone secretion. Verapamil blocks L-type calcium channels, causing coronary and peripheral vasodilation, and negative chronotropic/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.
Tarka (trandolapril/verapamil) is available as fixed-dose combinations: 1 mg/180 mg, 2 mg/180 mg, 2 mg/240 mg, 4 mg/240 mg. For hypertension, initial dose is 1 mg/180 mg orally once daily; titrate based on blood pressure response, maximum dose 8 mg/480 mg per day.
Oral: 120-360 mg once daily; maximum 540 mg daily.
None Documented
None Documented
Trandolaprilat terminal t1/2 16–24 h (prolonged in renal impairment, e.g., CrCl <30 mL/min ~36 h); verapamil t1/2 6–12 h (active metabolite norverapamil t1/2 ~12 h)
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
Renal: trandolaprilat 33% (unchanged 13%), trandolapril 10%; fecal: 66% (trandolaprilat 21%, trandolapril 33%); verapamil: renal 70% (16% unchanged), fecal 16%
Renal (2-4% unchanged, 60% as inactive metabolites); Fecal (30%); Biliary (minor)
Category C
Category C
ACE Inhibitor + Calcium Channel Blocker
Calcium Channel Blocker