Gemisartan CH Tablet is a combination antihypertensive medication containing Telmisartan 40 mg and Chlorthalidone 12.5 mg. Telmisartan is an angiotensin II receptor antagonist that selectively blocks the binding of angiotensin II to the AT1 receptor, thereby inhibiting vasoconstriction and aldosterone secretion, which results in vasodilation and reduction of blood pressure. Chlorthalidone is a thiazide-like diuretic that promotes diuresis by inhibiting sodium and chloride reabsorption in the distal convoluted tubules of the kidneys, leading to decreased plasma volume and peripheral vascular resistance. The synergistic effect of these two agents provides effective and sustained control of hypertension, reducing the risk of cardiovascular morbidity and mortality. Gemisartan CH is indicated for the treatment of essential hypertension, particularly in patients who require combination therapy to achieve target blood pressure. It is also beneficial in patients with salt-sensitive hypertension or volume-dependent hypertension due to its diuretic component. The combination improves patient compliance by reducing pill burden. Caution is advised in patients with renal or hepatic impairment, electrolyte imbalances, or hypersensitivity to sulfonamides. Regular monitoring of blood pressure, renal function, and electrolytes is recommended during therapy to ensure safety and efficacy.