Ambrisentan: uses, dosing, side effects & brands
Ambrisentan is an endothelin receptor antagonist sold in the U.S. under 2 brand and generic names, for pulmonary hypertension. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Drug class
- Endothelin Receptor Antagonist
- Treats
- Pulmonary Hypertension
- Available as
- Tablet
- Sold as
- 2 products — Letairis and Ambrisentan
- Prescription?
- Prescription only
- Generic available?
- Yes
- What the pharmacy pays
- about $256 for a 30-count supply — not your price
- Boxed warning
- Boxed warning
How ambrisentan is dosed
From the FDA label for Letairis (application NDA022081). Other ambrisentan products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Initiate treatment at 5 mg once daily ( 2.1 ). May be started with tadalafil ( 2.1 ). Titrate at 4-week intervals as needed and tolerated ( 2.1 ). Do not split, crush, or chew tablets ( 2.1 ). 2.1 Adult Dosage Initiate treatment at 5 mg once daily, with or without tadalafil 20 mg once daily. At 4-week intervals, either the dose of Letairis or tadalafil can be increased, as needed and tolerated, to Letairis 10 mg or tadalafil 40 mg. Do not split, crush, or chew tablets. 2.2 Pregnancy Testing in Females of Reproductive Potential Exclude pregnancy before initiating treatment with Letairis in females of reproductive potential [see Warnings and Precautions (5.1) , Use in Specific Populations (8.1 , 8.3) ].
Ambrisentan side effects
Clinically significant adverse reactions that appear in other sections of the labeling include: Embryo-fetal Toxicity [see Warnings and Precautions (5.1) , Use in Specific Populations (8.1) ] Fluid Retention [see Warnings and Precautions (5.2) ] Pulmonary Edema with PVOD [see Warnings and Precautions (5.3) ] Decreased Sperm Count [see Warnings and Precautions (5.4) ] Hematologic Changes [see Warnings and Precautions (5.5) ] Most common adverse reactions (>3% compared to placebo) are peripheral edema, nasal congestion, sinusitis, and flushing ( 6.1 ). When used in combination with tadalafil, most common adverse reactions (>5% compared with either monotherapy) are peripheral edema, headache, nasal congestion, cough, anemia, dyspepsia, and bronchitis ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Gilead Sciences, Inc. at (1-800-445-3235, Option 3) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Safety data for Letairis are presented from two 12-week, placebo-controlled studies (ARIES-1 and ARIES-2) in patients with pulmonary arterial hypertension (PAH), and one randomized,…
Who shouldn’t take ambrisentan
Pregnancy ( 4.1 ) Idiopathic Pulmonary Fibrosis ( 4.2 ) 4.1 Pregnancy Letairis may cause fetal harm when administered to a pregnant female. Letairis is contraindicated in females who are pregnant. Letairis was consistently shown to have teratogenic effects when administered to animals. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to a fetus [see Dosage and Administration (2.2) , Warnings and Precautions (5.1) , and Use in Specific Populations (8.1) ] . 4.2 Idiopathic Pulmonary Fibrosis Letairis is contraindicated in patients with Idiopathic Pulmonary Fibrosis (IPF), including IPF patients with pulmonary hypertension (WHO Group 3) [see Clinical Studies (14.4) ].
Ambrisentan drug interactions
Multiple dose coadministration of ambrisentan and cyclosporine resulted in an approximately 2-fold increase in ambrisentan exposure in healthy volunteers; therefore, limit the dose of ambrisentan to 5 mg once daily when coadministered with cyclosporine [see Clinical Pharmacology (12.3) ] . Cyclosporine increases ambrisentan exposure; limit ambrisentan dose to 5 mg once daily ( 7 ).
Every ambrisentan product we track (2)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
| # | Drug | Rating | Type | Form | Generic? | Pharmacy pays | |
|---|---|---|---|---|---|---|---|
| 1 | 70/100 | Prescription | Tablet | Generic | $256 | View → | |
| 2 | 66/100 | Prescription | Tablet | Generic | $256 | View → |
What ambrisentan pills look like
Imprint codes, colour and shape from the FDA’s labelling data. Match the imprint on your pill — or search any imprint.
Can you crush or split ambrisentan?
At least one ambrisentanproduct is labelled to be swallowed whole — crushing an extended-release tablet releases the whole day’s dose at once. Which applies depends on the form you were given.
What each ambrisentan label says about crushing, splitting and chewingHow long ambrisentan keeps
No ambrisentan label we read sets a separate limit for after opening, but they do specify how it must be stored — and the stability behind any date assumes those conditions.
Does ambrisentan expire? The in-use limits and storage rules from its labelsWhat people report to the FDA about ambrisentan
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 64,088 reports naming ambrisentan, and the FDA flagged 79% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- dyspnoea9,461 reports
- headache5,824 reports
- pneumonia4,479 reports
- diarrhoea4,090 reports
- nausea3,458 reports
- fatigue3,357 reports
- dizziness3,130 reports
- malaise2,657 reports
Read these as a signal, not a rate. A report does not mean ambrisentan caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
Related calculators
Frequently asked questions
What is ambrisentan?
Letairis (Ambrisentan) is an endothelin receptor antagonist used to treat Pulmonary Hypertension.
What kind of drug is ambrisentan?
The FDA classifies ambrisentan as an endothelin receptor antagonist. Endothelin receptor antagonists block endothelin-1, a natural substance that powerfully tightens blood vessels. By stopping it from acting on its receptors, these drugs let vessels relax and widen, lowering pressure in the lung arteries in conditions like pulmonary arterial hypertension. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.
Can you take ambrisentan with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run ambrisentan against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What brand names is ambrisentan sold under?
We track 2 ambrisentan-containing products in the U.S.: Letairis and Ambrisentan. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.
What forms does ambrisentan come in?
Across the brands we track, ambrisentan is currently marketed as tablet, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic ambrisentan?
Yes. Our catalog lists 1 generic ambrisentan product alongside the brand versions. A generic has the same active ingredient and must meet the FDA's bioequivalence standard; it usually costs less. Ask your pharmacist which one your plan covers.
Cite this page
- APA
- pharmaranks. (2026, July 24). Ambrisentan: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/ambrisentan
- MLA
- “Ambrisentan: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/ambrisentan.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for ambrisentan on DailyMed (NIH) ↗ — including its boxed warning in full.