Losartan is a medication used to treat high blood pressure. It is also used for diabetic kidney disease, heart failure, and left ventricular enlargement.Losartan was patented in 1986, and approved for medical use in the United States in 1995. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication.
Losartan was the first nonpeptide imidazole to beintroduced as an orally active angiotensin II antagonist withhigh specificity for AT1. When administered to patients, itundergoes extensive first-pass metabolism, with the 5-methanol being oxidized to a carboxylic acid. This metabolismis mediated by CYP 2C9 and 3A4 isozymes. The 5-methanol metabolite is approximately 15 times more potentthan the parent hydroxyl compound. Because the parent hydroxylcompound has affinity for the AT1 receptor, strictlyspeaking, it is not a prodrug.
