Comparative Pharmacology
Head-to-head clinical analysis: AVALIDE versus VALSARTAN AND HYDROCHLOROTHIAZIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AVALIDE versus VALSARTAN AND HYDROCHLOROTHIAZIDE.
AVALIDE vs VALSARTAN AND HYDROCHLOROTHIAZIDE
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.
Valsartan is an angiotensin II receptor blocker (ARB) that selectively inhibits the binding of angiotensin II to the AT1 receptor, thereby antagonizing angiotensin II-induced vasoconstriction, aldosterone secretion, and renal sodium reabsorption. Hydrochlorothiazide is a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, reducing sodium and water reabsorption.
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, one tablet once daily. Starting dose: 160/12.5 mg or 80/12.5 mg. Titrate to 160/25 mg or 320/12.5 mg-320/25 mg based on response. Max: 320/25 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.
Valsartan: Terminal half-life ~6 hours; Hydrochlorothiazide: Terminal half-life ~6-15 hours (prolonged in renal impairment).
Renal: HCTZ ~70% unchanged; Irbesartan ~20% unchanged, remainder as metabolites via biliary (60%) and renal (20%). Combined: Renal ~50%, biliary/fecal ~50%.
Valsartan: 83% eliminated via feces (biliary), 13% via urine; Hydrochlorothiazide: ≥95% eliminated unchanged via urine.
Category C
Category D/X
ARB and Thiazide Diuretic Combination
ARB