Comparative Pharmacology
Head-to-head clinical analysis: AVALIDE versus HYDROCHLOROTHIAZIDE VALSARTAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AVALIDE versus HYDROCHLOROTHIAZIDE VALSARTAN.
AVALIDE vs HYDROCHLOROTHIAZIDE; VALSARTAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Avalide is a combination of an angiotensin II receptor blocker (irbesartan) and a thiazide diuretic (hydrochlorothiazide). Irbesartan blocks the vasoconstrictor and aldosterone-secreting effects of angiotensin II by selectively antagonizing the AT1 receptor. Hydrochlorothiazide increases sodium and water excretion by inhibiting the Na+/Cl- symporter in the distal convoluted tubule.
Hydrochlorothiazide is a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, reducing sodium and water reabsorption. Valsartan is an angiotensin II receptor blocker (ARB) that selectively blocks the binding of angiotensin II to AT1 receptors, causing vasodilation and reduced aldosterone secretion.
AVALIDE (irbesartan/hydrochlorothiazide) is available as tablets containing 150/12.5 mg, 300/12.5 mg, or 300/25 mg. The typical starting dose is 150/12.5 mg once daily, titrated to 300/12.5 mg once daily as needed. Maximum dose is 300/25 mg once daily.
Oral, 12.5-25 mg hydrochlorothiazide / 80-320 mg valsartan once daily. Maximum dose: 25 mg hydrochlorothiazide / 320 mg valsartan per day.
None Documented
None Documented
Irbesartan: 11-15 h (terminal), HCTZ: 6-15 h (terminal). Clinical context: Steady state reached in 3-5 days; allows once-daily dosing.
Hydrochlorothiazide: 6-15 hours (terminal); clinical effect persists due to tubular secretion. Valsartan: 6 hours (terminal); no accumulation with once-daily dosing.
Renal: HCTZ ~70% unchanged; Irbesartan ~20% unchanged, remainder as metabolites via biliary (60%) and renal (20%). Combined: Renal ~50%, biliary/fecal ~50%.
Hydrochlorothiazide: ~70% renal (unchanged) via tubular secretion; ~30% biliary/fecal. Valsartan: 83% fecal (unchanged); 13% renal (unchanged and metabolites).
Category C
Category D/X
ARB and Thiazide Diuretic Combination
ARB