Lisilopril is an antihypertensive medication that belongs to the class of drugs known as ACE inhibitors (angiotensin-converting enzyme inhibitors). It is primarily used to treat high blood pressure (hypertension) and to improve survival after heart attacks. By relaxing blood vessels and reducing the workload on the heart, lisinopril helps to lower blood pressure and improve overall cardiovascular health. Common side effects may include cough, elevated potassium levels, and dizziness.