olmesartan

Olmesartan is an oral antihypertensive medication in the angiotensin II receptor blocker (ARB) class. It is used to treat adults with essential hypertension and may be used in combination with other antihypertensives to help achieve blood pressure targets.

Olmesartan works by selectively blocking the angiotensin II type 1 (AT1) receptor, which reduces vasoconstriction and aldosterone secretion, leading to a decrease in blood pressure. It is administered as the prodrug olmesartan medoxomil, which is hydrolyzed in the gut to the active metabolite olmesartan.

Pharmacokinetically, after oral administration, the median time to peak concentration is about 1–2 hours for the active drug. Bioavailability is roughly 25–35%, and the elimination half-life is around 10–15 hours. Olmesartan is largely excreted via the bile and urine with limited hepatic metabolism.

Dosing typically starts at 20 mg once daily, with potential titration to 40 mg once daily based on response and tolerability. The maximum recommended daily dose is 40 mg. Dosing adjustments may be considered in certain renal or hepatic conditions, and guidance should follow local labeling.

Safety and adverse effects: common side effects include dizziness, hyperkalemia, and upper respiratory tract infections. Angioedema is rare but possible. Olmesartan generally has a lower incidence of cough compared with ACE inhibitors. It is contraindicated in pregnancy and should be avoided during breastfeeding.