Comparative Pharmacology
Head-to-head clinical analysis: ENALAPRIL MALEATE AND HYDROCHLOROTHIAZIDE versus METAHYDRIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ENALAPRIL MALEATE AND HYDROCHLOROTHIAZIDE versus METAHYDRIN.
ENALAPRIL MALEATE AND HYDROCHLOROTHIAZIDE vs METAHYDRIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Enalapril is an angiotensin-converting enzyme (ACE) inhibitor that inhibits the conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone secretion, leading to decreased blood pressure. Hydrochlorothiazide is a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, increasing sodium, chloride, and water excretion, and reducing peripheral vascular resistance.
Metahydrin (trichlormethiazide) is a thiazide diuretic that inhibits the sodium-chloride symporter (NCC) in the distal convoluted tubule of the nephron, reducing sodium and chloride reabsorption and increasing excretion of water, sodium, chloride, and potassium.
Oral: Initially enalapril 5 mg and HCTZ 12.5 mg once daily; titrate to maximum enalapril 20 mg / HCTZ 25 mg once daily.
Oral, 50-100 mg once daily. Maximum 200 mg/day.
None Documented
None Documented
Enalaprilat: terminal 11 hours (multiple doses), prolonged in renal impairment (creatinine clearance <30 mL/min: 30-40 h). Hydrochlorothiazide: terminal 6-15 hours (mean 10 h), prolonged in renal impairment.
18-30 hours (clinically relevant for once-daily dosing in hypertension; prolonged in renal impairment)
Enalapril: renal 60-80% (40-60% as enalaprilat, 20-40% as metabolites); fecal 20-40%. Hydrochlorothiazide: renal 95% (unchanged).
Renal: 30% (fecal: 70% as unabsorbed drug, primarily biliary elimination; <1% unchanged in urine)
Category A/B
Category C
Thiazide Diuretic
Thiazide Diuretic