Losartan (rINN) (IPA: ) is an angiotensin II receptor antagonist drug used mainly to treat high blood pressure (hypertension). Losartan was the first angiotensin II receptor antagonist to be marketed. It is currently marketed by Merck & Co. under the trade name Cozaar.

Cozaar and Hyzaar - Losartan potassium and losartan potassium with hydrochlorothiazide. Features hypertension resources, prescribing information, and clinical data.
DrugDigest: Losartan ( Cozaar ) - Information on dosage, usage, side effects, interactions, and drug comparisons, including generics when available.
Hyzaar - Information about an antihypertension medication to treat hypertension or high blood pressure.
MEDLINEplus: Losartan - Information about dosage, usage, and side effects.
Meta Description: [ Losartan (Systemic) ]
MEDLINEplus: Losartan and Hydrochlorothiazide - Information about dosage, usage, and side effects.
Meta Description: [ Losartan and Hydrochlorothiazide ]