Medications guide

Lisinopril

Lisinopril is a prescription medicine in the ACE inhibitor class, used to treat high blood pressure and heart failure and to improve survival after a heart attack. This guide gives general information only.

Last updated 3 sources

At a Glance

  • Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor.
  • It relaxes blood vessels, which lowers blood pressure and eases the heart’s workload.
  • A dry, persistent cough is a well-known side effect of ACE inhibitors.
  • A rare but serious reaction called angioedema causes swelling of the face, lips, tongue, or throat.
  • The FDA label carries a boxed warning against use during pregnancy.
  • Kidney function and potassium levels are usually monitored with blood tests.

What It Is

Lisinopril is an oral medicine available as tablets and as a liquid. It is one of the most commonly prescribed blood pressure medicines in the United States.

ACE inhibitors like lisinopril are used for high blood pressure, heart failure, and after a heart attack. They are also often used in people with diabetes and kidney disease because of their protective effects on the kidneys.

General mechanism

Lisinopril blocks angiotensin-converting enzyme, which normally converts angiotensin I into angiotensin II, a hormone that tightens blood vessels and signals the body to retain salt and water. By reducing angiotensin II, lisinopril lets blood vessels relax and lowers fluid retention, which lowers blood pressure and reduces the workload on the heart. The same enzyme also breaks down bradykinin, and higher bradykinin levels are thought to explain the dry cough and, rarely, angioedema.

Common Terminology

ACE inhibitor
A class of medicines that block angiotensin-converting enzyme, reducing a hormone that narrows blood vessels.
Angiotensin II
A hormone that tightens blood vessels and raises blood pressure.
Angioedema
Swelling under the skin, often of the face, lips, tongue, or throat, which can be serious if it affects breathing.
Hyperkalemia
A higher-than-normal level of potassium in the blood.
Hypotension
Blood pressure that is lower than normal, which can cause dizziness or lightheadedness.
Heart failure
A condition in which the heart does not pump blood as well as it should.

General Uses

Lisinopril is prescribed for several established purposes.

  • Treating high blood pressure (hypertension) in adults and some children.
  • Treating heart failure, usually alongside other medicines.
  • Improving survival when started soon after a heart attack in suitable patients.
  • It is sometimes used to help protect kidney function in people with diabetes, at a clinician’s discretion.

Common Side Effects

Commonly reported side effects in general references include:

  • A dry, tickly cough that does not go away.
  • Dizziness or lightheadedness, especially when standing up.
  • Headache.
  • Tiredness.
  • Higher potassium levels on blood tests.

Common Warnings and Precautions

Medication labels and health agencies describe several general warnings.

  • The FDA label includes a boxed warning: medicines that act on the renin-angiotensin system can cause injury or death to a developing baby, so lisinopril is not used during pregnancy.
  • Angioedema, swelling of the face, lips, tongue, or throat, is rare but can be life-threatening; difficulty breathing or swallowing is generally treated as a medical emergency, and in the US people are advised to call 911.
  • Kidney function and potassium levels are typically checked with blood tests.
  • Potassium supplements, salt substitutes containing potassium, and some other medicines can raise potassium further.
  • Dehydration, vomiting, or diarrhea can increase the risk of low blood pressure and kidney problems.
  • Certain pain relievers called NSAIDs can reduce its effect and affect the kidneys when used together.

How It Works and How It Is Generally Used

This section describes general mechanism and use only; it does not include dosing information.

  • Lisinopril blocks the enzyme that makes angiotensin II, a hormone that narrows blood vessels.
  • With less angiotensin II, blood vessels relax and widen, lowering blood pressure.
  • It also reduces the release of aldosterone, a hormone that makes the body hold on to salt and water.
  • It is taken by mouth, with the product, amount, and schedule set by the prescriber and shown on the label.
  • Blood pressure readings and blood tests are commonly used to follow how it is working.

Questions Often Discussed With a Clinician or Pharmacist

People often raise topics like these about lisinopril.

  • What blood pressure readings are being aimed for.
  • How kidney function and potassium will be monitored.
  • What to know about the cough side effect.
  • Warning signs of angioedema and what they mean.
  • Pregnancy plans and contraception, given the boxed warning.
  • Interactions with NSAIDs, potassium supplements, or salt substitutes.

Questions to Ask a Healthcare Professional

General questions people often find useful to bring to an appointment:

  • What is lisinopril meant to do for my heart or blood pressure?
  • How often will my blood pressure and blood tests be checked?
  • Is a cough from this medicine common, and what are the options if it happens?
  • What are the warning signs of a serious allergic-type reaction?
  • Which over-the-counter medicines or salt substitutes could interact with it?
  • What should I know about this medicine and pregnancy?

Sources

This guide was written in plain language from the following authoritative references.

  1. Lisinopril — MedlinePlus (U.S. National Library of Medicine)
  2. Lisinopril — NHS (UK National Health Service)
  3. Blood Pressure Medicines — MedlinePlus (U.S. National Library of Medicine)

Last updated October 8, 2026. FreeDoc guides are general educational information and are not a substitute for care from a qualified professional.