Comparative Pharmacology
Head-to-head clinical analysis: AMLODIPINE BESYLATE AND BENAZEPRIL HYDROCHLORIDE versus CAPOZIDE 50 15.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AMLODIPINE BESYLATE AND BENAZEPRIL HYDROCHLORIDE versus CAPOZIDE 50 15.
AMLODIPINE BESYLATE AND BENAZEPRIL HYDROCHLORIDE vs CAPOZIDE 50/15
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Amlodipine is a dihydropyridine calcium channel blocker that inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle, causing peripheral vasodilation and reduction of peripheral vascular resistance. Benazepril is a prodrug that is hydrolyzed to benazeprilat, a competitive inhibitor of angiotensin-converting enzyme (ACE), preventing conversion of angiotensin I to angiotensin II, thereby reducing vasoconstriction, aldosterone secretion, and sodium and water retention.
CAPOZIDE 50/15 combines captopril (angiotensin-converting enzyme inhibitor) and hydrochlorothiazide (thiazide diuretic). Captopril inhibits ACE, reducing angiotensin II formation, decreasing aldosterone secretion, and lowering blood pressure. Hydrochlorothiazide increases sodium and water excretion by inhibiting the Na+/Cl- cotransporter in distal convoluted tubules.
Oral, one capsule daily. Initial: 2.5 mg/10 mg for patients not on either drug; up to 10 mg/40 mg daily.
Oral, 1 tablet (captopril 50 mg / hydrochlorothiazide 15 mg) once daily. May increase to 2 tablets daily in divided doses if needed.
None Documented
None Documented
Amlodipine terminal half-life 30-50 hours (allows once-daily dosing; steady state reached after 7-10 days). Benazeprilat effective half-life 10-11 hours (accumulation minimal).
Captopril: terminal half-life ~2 hours (in patients with normal renal function; prolonged in renal impairment to 21-36 hours). Hydrochlorothiazide: half-life 6-15 hours (mean ~9 hours; prolonged in renal impairment). Clinical context: dosing interval affected by renal function.
Amlodipine: 60% renal (10% unchanged, rest as metabolites), 20-25% biliary/feces. Benazepril: 11-12% renal (as unchanged benazepril and benazeprilat), 85-90% biliary (as benazeprilat conjugates).
Captopril: renal excretion of unchanged drug and metabolites, primarily in urine (60-75%), with ~20% as unchanged captopril; small amount in feces (5-10%). Hydrochlorothiazide: renal excretion (95% unchanged), <5% via biliary/fecal.
Category D/X
Category C
ACE Inhibitor
ACE Inhibitor and Diuretic Combination