Comparative Pharmacology
Head-to-head clinical analysis: AMLODIPINE BESYLATE AND VALSARTAN versus AVALIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AMLODIPINE BESYLATE AND VALSARTAN versus AVALIDE.
AMLODIPINE BESYLATE AND VALSARTAN vs AVALIDE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Amlodipine is a dihydropyridine calcium channel blocker that inhibits the influx of calcium ions into vascular smooth muscle and cardiac muscle, causing vasodilation and reduced peripheral vascular resistance. Valsartan is an angiotensin II receptor blocker that selectively blocks the binding of angiotensin II to AT1 receptors, resulting in vasodilation and reduced aldosterone secretion.
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.
Adults: initial combination therapy 5/160 mg (amlodipine/valsartan) orally once daily; titrate based on response, maximum 10/320 mg once daily.
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.
None Documented
None Documented
Amlodipine: 30-50 hours (terminal); Valsartan: 6-9 hours. Amlodipine's long half-life allows once-daily dosing; steady state achieved after 7-10 days.
Irbesartan: 11-15 h (terminal), HCTZ: 6-15 h (terminal). Clinical context: Steady state reached in 3-5 days; allows once-daily dosing.
Amlodipine: ~60% renal (10% as unchanged drug), ~20-25% biliary/fecal. Valsartan: ~83% fecal via biliary, ~13% renal (mainly unchanged).
Renal: HCTZ ~70% unchanged; Irbesartan ~20% unchanged, remainder as metabolites via biliary (60%) and renal (20%). Combined: Renal ~50%, biliary/fecal ~50%.
Category D/X
Category C
ARB
ARB and Thiazide Diuretic Combination