Comparative Pharmacology
Head-to-head clinical analysis: CAPOTEN versus QUINAPRIL HYDROCHLORIDE AND HYDROCHLOROTHIAZIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CAPOTEN versus QUINAPRIL HYDROCHLORIDE AND HYDROCHLOROTHIAZIDE.
CAPOTEN vs QUINAPRIL HYDROCHLORIDE AND HYDROCHLOROTHIAZIDE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Competitive inhibitor of angiotensin-converting enzyme (ACE), preventing conversion of angiotensin I to angiotensin II, leading to decreased vasoconstriction, reduced aldosterone secretion, and increased plasma renin activity.
Quinapril is an ACE inhibitor that inhibits the conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone secretion; hydrochlorothiazide is a thiazide diuretic that inhibits sodium reabsorption in the distal convoluted tubule, increasing excretion of sodium and water.
50 mg orally three times daily initially; maintenance 50-100 mg three times daily; maximum 450 mg/day.
Initial: 10/12.5 mg (quinapril/hydrochlorothiazide) orally once daily. Titrate based on response to a maximum of 40/25 mg once daily.
None Documented
None Documented
Terminal elimination half-life is approximately 1.9 hours in healthy subjects, but prolonged in heart failure (up to 3-4 hours) and renal impairment (up to 5-10 hours).
Quinaprilat terminal half-life ~25 hours (effective half-life ~12 hours); hydrochlorothiazide ~6-15 hours (increased in renal impairment).
Primarily renal (approximately 60-75% as unchanged drug and metabolites) and biliary/fecal (approximately 20%).
Renal excretion of quinaprilat (active metabolite) ~50-60% unchanged; hydrochlorothiazide ~70% unchanged. Biliary/fecal elimination accounts for <10% for both components.
Category C
Category D/X
ACE Inhibitor
ACE Inhibitor