Font Size

Medications and Drugs

Brand Names: Letairis

Generic Name: ambrisentan (Pronunciation: am bri SEN tan)

What is ambrisentan (Letairis)?

Ambrisentan prevents thickening of the blood vessels, especially those in the lungs and heart. Ambrisentan also lowers blood pressure in your lungs, helping your heart pump blood more efficiently.

Ambrisentan is used to treat pulmonary arterial hypertension (PAH). It improves your ability to exercise and prevents your condition from getting worse.

Ambrisentan may also be used for purposes not listed in this medication guide.

What are the possible side effects of ambrisentan (Letairis)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have a serious side effect such as:

  • anxiety, sweating, pale skin, severe shortness of breath, wheezing, gasping for breath, cough with foamy mucus, chest pain, fast or uneven heart rate;
  • swelling of the feet, ankles, or legs;
  • pounding heartbeats or fluttering in your chest; or
  • nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about ambrisentan (Letairis)?

Ambrisentan can harm an unborn baby or cause birth defects. Do not use if you are pregnant.

If you are a woman of child-bearing potential, you will need to have a negative pregnancy test before you start treatment with ambrisentan. You will also be re-tested each month during your treatment.

You will be required to use two forms of birth control to prevent pregnancy during your treatment, and for at least 1 month after your treatment ends. If you have had a tubal ligation or are using a copper IUD, you will not need to use a second form of birth control.

Do not stop taking ambrisentan without first talking to your doctor. You may need to use less and less before you stop the medication completely.

Ambrisentan is available only under a special program called LEAP (Letairis Education and Access Program). You must be registered in the program and sign agreements to use birth control and undergo pregnancy and blood testing as required by the program. Read all program brochures and agreements carefully.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Pill Identifier Tool

Need help identifying pills and medications?
Use the pill finder tool on RxList.

Medical Dictionary