Letairis Side Effects

Generic Name: ambrisentan

Note: This page contains information about the side effects of ambrisentan. Some of the dosage forms included on this document may not apply to the brand name Letairis.

Not all side effects for Letairis may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

For the Consumer

Applies to ambrisentan: oral tablet

In addition to its needed effects, some unwanted effects may be caused by ambrisentan (the active ingredient contained in Letairis). In the event that any of these side effects do occur, they may require medical attention.

You should check with your doctor immediately if any of these side effects occur when taking ambrisentan:

More common
  • Bloating or swelling of the face, arms, hands, lower legs, or feet
  • rapid weight gain
  • tingling of the hands or feet
  • unusual weight gain or loss
Less common
  • Cough
  • fast, irregular, pounding, or racing heartbeat or pulse
  • fever
  • headache
  • muscle aches
  • pain or tenderness around the eyes and cheekbones
  • sore throat
  • stuffy or runny nose
  • tightness of the chest
  • trouble breathing
  • unusual tiredness or weakness
Incidence not known
  • Abdominal or stomach pain or tenderness
  • chest pain
  • clay colored stools
  • dark urine
  • decrease in the amount of urine
  • decreased appetite
  • dilated neck veins
  • extreme fatigue
  • irregular breathing
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • loss of appetite
  • nausea and vomiting
  • noisy, rattling breathing
  • pale skin
  • skin rash, itching
  • troubled breathing at rest
  • troubled breathing with exertion
  • yellow skin or eyes

If any of the following symptoms of overdose occur while taking ambrisentan, get emergency help immediately:

Symptoms of overdose
  • Blurred vision
  • confusion
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • sweating

Some of the side effects that can occur with ambrisentan may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

Less common
  • Difficulty having a bowel movement (stool)
  • feeling of warmth
  • redness of the face, neck, arms, and occasionally, upper chest

For Healthcare Professionals

Applies to ambrisentan: oral tablet


Hepatic side effects have included dose-dependent liver injury manifested primarily by elevation of serum aminotransferases (ALT or AST), but sometimes accompanied by abnormal liver function (elevated bilirubin). The combination of aminotransferases greater than 3 times the upper limit of normal and total bilirubin 2 times the upper limit of normal is a marker for potentially serious hepatic injury.


Hematologic side effects have included decreases in hemoglobin concentration and hematocrit. Postmarketing reports have included anemia. There have been postmarketing reports of decreases in hemoglobin concentration and hematocrit that have resulted in anemia requiring transfusion. In the long-term open-label extension of the two pivotal clinical studies, mean decreases from baseline (ranging from 0.9 to 1.2 g/dL) in hemoglobin concentrations persisted for up to 4 years of treatment.


Cardiovascular side effects have included peripheral edema, palpitations, and flushing. Fluid retention has been reported during postmarketing use of ambrisentan (the active ingredient contained in Letairis) Additional postmarketing reports have included heart failure (associated with fluid retention).


Respiratory side effects have included dyspnea, nasal congestion, sinusitis, and nasopharyngitis.


Gastrointestinal side effects have included abdominal pain and constipation. Postmarketing experience has included nausea and vomiting.

Nervous system

Nervous system side effects have included headache, asthenia, dizziness, and fatigue.


Hypersensitivity side effects have included postmarketing reports of angioedema and rash.


Postmarketing reports: Decreased sperm counts

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. 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 substances you are taking, check with your doctor, nurse, or pharmacist.