About Valsartan Angiotensin II receptor antagonist, Antihypertensive. Mechanism of Action of Valsartan It is a competitive antagonist of angiotensin-2 at AT-1 receptor. It decreases peripheral resistance and lowers BP in hypertensive individuals. It blocks all overt actions of angiotensin-2 such as: - 1. Vasoconstriction, 2. Central & Peripheral sympathetic stimulus, 3. Release of aldosterone and adrenaline, 4. Salt and water reabsorption, 5. Central actions like thirst, vasopressin release, and growth promoting actions on heart and blood vessels. Indications for Valsartan 1. Hypertension Interactions for Valsartan Potassium-sparing diuretics (e.g., Spironolactone, Triamterene, Amiloride), Potassium supplements, or Salt substitutes containing potassium: Concomitant use of Valsartan with these drugs will result in hyperkalaemia and in heart failure patients it increases serum creatinine.