Lisinopril is an oral medication used to treat high blood pressure and heart failure. Learn about side effects, warnings, dosage, and more. Learn about common and rare lisinopril side effects and what to do if they occur. Lowering blood pressure can reduce the risk of strokes and heart attacks. Lisinopril is an angiotensin converting enzyme (ACE) inhibitor. It works by blocking a substance in the body that causes blood vessels to tighten. As a result, lisinopril relaxes the blood vessels. Lisinopril is a medication belonging to the drug class of angiotensin-converting enzyme (ACE) inhibitors and is used to treat hypertension (high blood pressure), heart failure, and heart attacks. [7] Lisinopril is an ACE inhibitor. It is used to treat high blood pressure, congestive heart failure in adults, or to improve survival after a heart attack. Find patient medical information for Lisinopril (Prinivil, Zestril, and Others) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings It is used in combination with other medications to treat heart failure. Lisinopril is also used to improve survival after a heart attack. Lisinopril is in a class of medications called angiotensin-converting enzyme (ACE) inhibitors. Detailed Lisinopril dosage information for adults, the elderly and children. Includes dosages for Hypertension, Congestive Heart Failure, Myocardial Infarction and more; plus renal, liver and dialysis adjustments. Lisinopril is used alone or together with other medicines to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. While the mechanism through which Lisinopril lowers blood pressure is believed to be primarily suppression of the renin-angiotensin-aldosterone system, Lisinopril is antihypertensive even in patients with low-renin hypertension.