Its empirical formula is C20H25ClN2O5•C6H6O3S and its molecular weight is 567.1.
Valsartan, USP is a nonpeptide, orally active, and specific angiotensin II antagonist acting on the AT1 receptor subtype. Valsartan is a white to practically white fine powder, soluble in ethanol and methanol and slightly soluble in water. Valsartan’s chemical name is N-(1-oxopentyl)-N-[[2′-(1H-tetrazol-5-yl) [1,1′-biphenyl]-4-yl]methyl]-L-valine; its structural formula is

Its empirical formula is C24H29N5O3 and its molecular weight is 435.5.
Hydrochlorothiazide, USP is a white, or practically white, practically odorless, crystalline powder. It is slightly soluble in water; freely soluble in sodium hydroxide solution, in n-butylamine, and in dimethylformamide; sparingly soluble in methanol; and insoluble in ether, in chloroform, and in dilute mineral acids. Hydrochlorothiazide is chemically described as 6-chloro-3,4-dihydro-2H-1,2,4-benzothiadiazine-7- sulfonamide 1,1-dioxide.
Hydrochlorothiazide is a thiazide diuretic. Its empirical formula is C7H8ClN3O4S2, its molecular weight is 297.73, and its structural formula is


Exforge HCT film-coated tablets are formulated in five strengths for oral administration with a combination of amlodipine besylate,valsartan and hydrochlorothiazide, providing for the following available combinations: 5/160/12.5 mg, 10/160/12.5 mg, 5/160/25 mg, 10/160/25 mg and 10/320/25 mg amlodipine besylate/valsartan/hydrochlorothiazide. The inactive ingredients for all strengths of the tablets includemicrocrystalline cellulose; crospovidone; colloidal anhydrous silica; magnesium stearate; hypromellose, macrogol 4000 and talc. Additionally, the 5/160/12.5 mg strength contains titanium dioxide; the 10/160/12.5 strength contains titanium dioxide and yellow and red iron oxides; the 5/160/25 mg strength contains titanium dioxide and yellow iron oxide and the 10/160/25 mg and 10/320/25 mg strengths both contain yellow iron oxide.
12 CLINICAL PHARMACOLOGY
12.1 Mechanism of Action
The active ingredients of Exforge HCT target three separate mechanisms involved in blood pressure regulation. Specifically, amlodipine blocks the contractile effects of calcium on cardiac and vascular smooth muscle cells; valsartan blocks the vasoconstriction and sodium retaining effects of angiotensin II on cardiac, vascular smooth muscle, adrenal and renal cells; and hydrochlorothiazide directly promotes the excretion of sodium and chloride in the kidney leading to reductions in intravascular volume. A more detailed description of the mechanis