Losartan is a generic drug used in the treatment of high blood pressure, according to WebMD. The drug is also used to protect the kidneys from damage in diabetics and to lower the risk of stroke in a patient with an enlarged heart.
Losartan belongs to a class of drugs known as angiotensin receptor blockers, says WebMD. The drug works by relaxing blood vessels, meaning that blood is able to pass through the body with less pressure.
Dizziness is a common initial side effect as the body becomes accustomed to the medication, according to WebMD. This risk is reduced if the patient moves slowly when rising from a sitting or lying position.