Irbesartan Pharmacology

Irbesartan is an angiotensin II receptor blocker (ARB) used primarily for the management of hypertension and diabetic nephropathy in type 2 diabetes. It selectively inhibits the binding of angiotensin II to the AT1 receptor found in vascular smooth muscle and the adrenal gland. This blockade results in vasodilation, reduced aldosterone secretion, decreased sodium and water retention, and ultimately lower blood pressure. Irbesartan is administered orally, with a typical starting dose of 150 mg once daily, which may be increased to 300 mg depending on the patient’s clinical response and tolerability. Adverse effects of irbesartan are generally mild but can include hyperkalemia and dizziness. Hypotension may occur, especially in volume-depleted individuals or those on diuretics. Routine monitoring of renal function and serum potassium is recommended, especially in patients with underlying kidney disease or those taking potassium-sparing agents or supplements. Irbesartan is contraindicated in pregnancy due to the risk of fetal toxicity and should be discontinued as soon as pregnancy is detected.