Ambrisentan
LETAIRIS
Pronunciation: am-bri-SEN-tan (le-TAIR-is)
What it isSelective endothelin A receptor antagonist; pulmonary arterial hypertension.
Why this oneOnce daily, and combined with tadalafil up front it improves outcomes more than either alone.
What limits itEmbryo-fetal toxicity under a REMS. Peripheral edema and anemia; it is contraindicated in idiopathic pulmonary fibrosis.
FDA-approved for
- pulmonary arterial hypertension (2007)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Pulmonary arterial hypertension (WHO Group 1) | Adult | 5 mg QD | 5–10 mg QD | 10 mg QD |
Titration May increase at 4-week intervals as needed and tolerated.
Renal No adjustment for mild–moderate impairment; no data in severe impairment.
Hepatic Not recommended in moderate or severe impairment; no data in mild.
Instructions
- Do not split, crush, or chew tablets.
- Obtain pregnancy test before initiation; use effective contraception.
- Measure hemoglobin at baseline, at 1 month, then periodically.
Available strengths
- tab 5, 10 mg
Contraindications
- Pregnancy
- Idiopathic pulmonary fibrosis (including IPF with pulmonary hypertension, WHO Group 3)
Cautions
- Fluid retention/peripheral edema (may need intervention)
- Pulmonary edema—consider pulmonary veno-occlusive disease
- Decreased sperm counts
- Decreases in hemoglobin/hematocrit; anemia can require transfusion
Adverse reactions
- Peripheral edema
- Nasal congestion
- Sinusitis
- Flushing
Pregnancy Contraindicated—may cause fetal harm, including birth defects and fetal death (teratogenic in animals).
Lactation Unknown whether present in human milk; decide whether to discontinue breastfeeding or the drug.
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 5 mg | tab | 30 qd | not offered | |
| 10 mg | tab | 30 qd | $240.74 | not offered |
Generic entry2019
⚠ BOXED WARNING
- Embryo-fetal toxicity
Classes and tags
Clinical profile
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.