6 mins read

Overview: Ambrisentan is an oral tablet used for pulmonary arterial hypertension. It helps lower blood pressure in the lungs. Common side effects include swelling due to fluid buildup, stuffy nose, and flushing. Ambrisentan may cause harm to a fetus if taken during pregnancy. Other serious side effects may include liver damage and low levels of red blood cells (anemia).

Uses

What is ambrisentan used for?

Ambrisentan is commonly used for pulmonary arterial hypertension (PAH). PAH is a condition where you have high pressure in the blood vessels (arteries) that carry blood into your lungs. Over time, this pressure strains your heart and makes it harder for you to be physically active.

Ambrisentan may also be used for other conditions as determined by your health care provider.

How does ambrisentan work (mechanism of action)?

Ambrisentan blocks endothelin-1, a substance that tightens blood vessels and worsens lung damage in people with pulmonary arterial hypertension. By blocking endothelin-1, ambrisentan helps relax the blood vessels and lower the blood pressure in the lungs. This can help prevent the damage from getting worse.

How is ambrisentan supplied (dosage forms)?

Brands and other names

  • Letairis

Dosage forms and strengths

  • 5 mg, 10 mg oral tablets

How should I store ambrisentan?

Ambrisentan should be stored in its original container at room temperature, between 68 F and 77 F (20 C and 25 C). It can be exposed to temperatures between 59 F and 86 F (15 C and 30 C) for shorter periods of time, such as when transporting it. Store in a cool, dry place.

Side Effects

What are the most common side effects of ambrisentan?

The most common side effects of ambrisentan are listed below. Tell your health care provider if you have any of these side effects that bother you.

  • Fluid retention or swelling in your hands, legs, feet, or other areas of your body (see below)
  • Stuffy nose, inflamed nasal passages (sinusitis), sore throat, or common cold symptoms
  • Flushing

There may be other side effects of ambrisentan that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of ambrisentan?

While less common, the most serious side effects of ambrisentan are described below, along with what to do if they happen.

Severe Allergic Reactions. Ambrisentan may cause allergic reactions, which can be serious. Stop taking ambrisentan and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching or skin rash
  • Bumps on the skin called hives, which can be red, pink, white, or brown depending on your skin tone
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Fluid Retention (Edema). Ambrisentan can cause fluid retention, also called edema. Fluid retention can cause serious issues in people with certain conditions, such as heart failure. Call your health care provider right away if you have any of the following symptoms.

  • Chest pain
  • Shortness of breath that is worse than usual
  • Stretched or shiny skin
  • Unusual weight gain
  • Swelling of your ankles, legs, belly, or other body areas

Anemia. Ambrisentan may cause anemia, which is when you have low levels of red blood cells and low hemoglobin. Hemoglobin is a protein in red blood cells that carries oxygen throughout your body. Keep all appointments for blood tests while you are taking ambrisentan. Tell your health care provider if you have any of the following symptoms of anemia.

  • Unusual weakness or tiredness
  • Cold hands and feet
  • Fast or abnormal heartbeat
  • Pale or yellowish skin 
  • Dizziness, lightheadedness, or feeling like you are about to pass out

Liver Damage. Liver damage, also called hepatotoxicity, may happen while taking ambrisentan. Keep all lab test appointments to monitor for signs of liver problems. Call your health care provider right away if you have any of the following symptoms of liver damage.

  • Nausea or vomiting
  • Stomach or belly pain
  • Fever
  • Weakness or unusual tiredness
  • Itching
  • Loss of appetite
  • Light-colored poop
  • Dark-colored urine (pee)

Your skin or the whites of your eyes turning yellowish (also called jaundice)

Warnings & Precautions

Who should not use ambrisentan?

Allergies to Ingredients. People who are allergic to any of the following should not take ambrisentan.

  • Ambrisentan
  • Letairis
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific ambrisentan products they stock.

Pregnancy. Do not take ambrisentan if you are pregnant or plan to become pregnant. If you become pregnant or think you might be pregnant, contact your health care provider right away. See the Pregnancy section for more details.

Lung Fibrosis. Do not take ambrisentan if you have a serious lung problem called idiopathic pulmonary fibrosis. Taking ambrisentan could make this condition worse.

What should I know about ambrisentan before taking it?

Do not take ambrisentan unless it has been prescribed to you by a health care provider. Take it as prescribed.

Do not share ambrisentan with other people, even if they have the same condition as you. It may harm them.

Keep ambrisentan out of the reach of children.

Do not split, crush, or chew ambrisentan.

Ambrisentan may lower sperm count and could make it hard for you to get your partner pregnant. If you have concerns, talk to your health care provider.

People who are aged 65 or older can be at greater risk of some side effects from ambrisentan. Talk to your health care provider about your risks if you are in this age group.

What should I tell my health care provider before taking ambrisentan?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if ambrisentan is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your health care provider if you have any of the following.

  • Low red blood cell levels (anemia)
  • Liver problems
  • Heart failure
  • Pulmonary veno-occlusive disease, a condition where certain blood vessels in the lungs are blocked or narrowed

Other Medicines and Supplements. Ambrisentan may interact with other medicines and supplements. Before taking ambrisentan, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. Ambrisentan may cause harm to a fetus. You must not be pregnant before starting ambrisentan. If you can become pregnant, you must use effective birth control before starting ambrisentan, while taking it, and for one month after your last dose. Talk to your health care provider about your birth control options. If you become pregnant or think you might be pregnant, contact your health care provider right away. 

Breastfeeding. Do not take ambrisentan while you are breastfeeding. It is not known if ambrisentan passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.

Interactions

Does ambrisentan interact with foods or drinks?

There are no known interactions between ambrisentan and foods or drinks.

It is unknown if drinking alcohol will affect ambrisentan. The risk of certain side effects, such as liver problems, may be higher if you drink alcohol while taking ambrisentan.

Does ambrisentan interact with other medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are taking cyclosporine (Gengraf, Neoral, Sandimmune, and others), which is a medicine that suppresses your immune system.

Some other medicines may alter the blood levels of ambrisentan, and vice versa. Tell your health care provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with ambrisentan. Always check with your health care provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much ambrisentan?

If you or someone else has taken too much ambrisentan, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of ambrisentan?

If you miss a dose, take it as soon as you remember that same day. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.