Losartan potassium (LOSAR) is a medicine used to treat high blood pressure and heart failure. It works by blocking the action of hormones in the body that raise blood pressure. LOSAR is available as tablets in doses of 25, 50 and 100 mg. It is easy to take and has been shown to be safe, effective and well tolerated. Buy LOSAR now in our online store and have it delivered directly to your home.