Comparative Pharmacology
Head-to-head clinical analysis: TARKA versus VERELAN PM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: TARKA versus VERELAN PM.
TARKA vs VERELAN PM
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.
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.
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.
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
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 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: trandolaprilat 33% (unchanged 13%), trandolapril 10%; fecal: 66% (trandolaprilat 21%, trandolapril 33%); verapamil: renal 70% (16% unchanged), fecal 16%
Primarily hepatic metabolism (>95%), with 3-4% excreted unchanged in urine; biliary/fecal excretion accounts for <1% of unchanged drug.
Category C
Category C
ACE Inhibitor + Calcium Channel Blocker
Calcium Channel Blocker