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Generic Name: ambrisentan (AM bri SEN tan)
Brand Name: Letairis

What is ambrisentan?

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 is sometimes used with a medicine called tadalafil (Adcirca).

Ambrisentan is available only from a certified pharmacy 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.

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

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

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 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 (unless you have had a tubal ligation or are using a copper IUD).

You should not use this medication if you have idiopathic pulmonary fibrosis (IPF).

Ambrisentan is available only from a certified pharmacy under a special program.

What should I discuss with my healthcare provider before taking ambrisentan?

You should not use this medication if you are allergic to ambrisentan, or if you have idiopathic pulmonary fibrosis (IPF).

To make sure ambrisentan is safe for you, tell your doctor if you have:

  • anemia (low red blood cell counts);

  • liver disease; or

  • if you are pregnant or plan to become pregnant while taking ambrisentan.

This medicine can harm an unborn baby or cause birth defects. Do not use if you are pregnant, and tell your doctor right away if you become 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 must use two forms of birth control to prevent pregnancy during your treatment, and for at least 1 month after your last dose. If you have had a tubal ligation or use a copper IUD (intrauterine device) or progesterone implant, you will not need to use a second form of birth control.

Recommended combinations of birth control forms include:

  • one hormone form (birth control pill, skin patch, implant, vaginal ring, or injection) plus 1 barrier form (condom, diaphragm with spermicide, or cervical cap with spermicide);

  • a condom and a female barrier form together (diaphragm with spermicide, or cervical cap with spermicide); or

  • a partner's vasectomy plus 1 hormone form or 1 barrier form.

Talk with your doctor about the use of emergency contraception if you have unprotected sex or if you believe your form of contraception has failed.

It is not known whether ambrisentan passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are using ambrisentan.

Ambrisentan may lower a man's sperm count and could affect fertility (your ability to have children).

How should I take ambrisentan?

Before you start treatment with ambrisentan, your doctor may perform blood tests to make sure it is safe for you to take this medicine. Your blood will need to be tested often during treatment.

Ambrisentan is usually taken once daily. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Ambrisentan can be taken with or without food. Take the medicine at the same time each day.

Do not crush, chew, or split the tablet. Swallow the pill whole.

Store at room temperature away from moisture and heat. Keep this medicine in its original container.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using ambrisentan?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Ambrisentan side effects

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

Call your doctor at once if you have:

  • severe shortness of breath, wheezing, cough with foamy mucus, chest pain;

  • swelling, rapid weight gain; or

  • low red blood cells (anemia)--pale skin, feeling light-headed or short of breath, rapid heart rate, trouble concentrating.

Common side effects may include:

  • anemia;

  • swelling in your hands or feet;

  • headache;

  • cough, stuffy nose, sinus pain; or

  • flushing (warmth, redness, or tingly feeling).

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.

See also: Side effects (in more detail)

Ambrisentan dosing information

Usual Adult Dose for Pulmonary Hypertension:

Initial dose: 5 mg orally once a day.

-Consider increasing the dose to 10 mg orally once a day if 5 mg is tolerated.
-When used with tadalafil, the dose of either drug can be increased as needed and tolerated at 4-week intervals.

-For the treatment of pulmonary arterial hypertension (WHO Group 1) to improve exercise ability and delay clinical worsening.
-For the treatment of pulmonary arterial hypertension (WHO Group 1) in combination with tadalafil to reduce the risks of disease progression and hospitalization for worsening pulmonary arterial hypertension, and to improve exercise ability.

What other drugs will affect ambrisentan?

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • cyclosporine.

This list is not complete. Other drugs may interact with ambrisentan, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your doctor or pharmacist can provide more information about ambrisentan.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 8.01.

Last reviewed: October 22, 2015
Date modified: October 14, 2016