Comparative Pharmacology
Head-to-head clinical analysis: AVALIDE versus HYDROCHLOROTHIAZIDE IRBESARTAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AVALIDE versus HYDROCHLOROTHIAZIDE IRBESARTAN.
AVALIDE vs HYDROCHLOROTHIAZIDE; IRBESARTAN
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. Irbesartan is an angiotensin II receptor blocker (ARB) that selectively inhibits the AT1 receptor, blocking vasoconstriction and 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.
Hydrochlorothiazide 12.5-25 mg and irbesartan 150-300 mg orally once daily. Maximum dose: hydrochlorothiazide 25 mg/day; irbesartan 300 mg/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 (prolonged in renal impairment); Irbesartan: 11-15 hours (supports 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%.
Renal: 70% (irbesartan, unchanged and metabolites); 95% (hydrochlorothiazide, unchanged). Fecal: 30% (irbesartan).
Category C
Category D/X
ARB and Thiazide Diuretic Combination
ARB