Ambrisentan vs Macitentan: side effects in FDA adverse event reports
At a glance
| Ambrisentan | Macitentan | |
|---|---|---|
| Drug class | Endothelin Receptor Antagonist | Endothelin Receptor Antagonist |
| Brand names | – | – |
| FAERS reports | 124,082 | 68,750 |
| Serious | 65% | 71% |
| Death outcome | 17,005 | 12,527 |
| Boxed warning | Yes EMBRYO-FETAL TOXICITY Ambrisentan tablets are contraindicated for use during pregnancy because it may cause major birth defects if used by pregnant patients, ba | Yes EMBRYO-FETAL TOXICITY Macitentan tablets are contraindicated for use during pregnancy because it may cause fetal harm based on animal data [see Contraindication |
Signals both drugs share
| Reaction | Ambrisentan | Macitentan | Label screen (A / B) |
|---|---|---|---|
| Right ventricular failure | 1,240 · PRR 35.8 | 1,292 · PRR 68.1 | Not in label — unassessed / Labeled (related wording) |
| Infusion site infection | 490 · PRR 46.5 | 396 · PRR 64.4 | Not in label — unassessed / Labeled (related wording) |
| Pulmonary veno-occlusive disease | 92 · PRR 25.6 | 125 · PRR 66.6 | Labeled — boxed warning / Labeled — boxed warning |
| Pulmonary arterial hypertension | 3,352 · PRR 50.4 | 3,291 · PRR 89.0 | Likely indication confounding / Likely indication confounding |
| Catheter site erythema | 328 · PRR 31.3 | 417 · PRR 75.7 | Not in label — unassessed / Not in label — unassessed |
| Infusion site discharge | 298 · PRR 35.5 | 271 · PRR 57.3 | Not in label — unassessed / Not in label — unassessed |
| Catheter site pruritus | 207 · PRR 52.2 | 276 · PRR 140.6 | Not in label — unassessed / Not in label — unassessed |
| Catheter site discharge | 204 · PRR 38.3 | 214 · PRR 73.5 | Not in label — unassessed / Not in label — unassessed |
| Infusion site irritation | 174 · PRR 27.4 | 175 · PRR 49.8 | Not in label — unassessed / Not in label — unassessed |
| Infusion site warmth | 165 · PRR 26.8 | 170 · PRR 50.1 | Not in label — unassessed / Not in label — unassessed |
| Transplant evaluation | 133 · PRR 59.4 | 149 · PRR 125.7 | Not in label — unassessed / Not in label — unassessed |
| Catheter site rash | 90 · PRR 42.0 | 143 · PRR 141.9 | Not in label — unassessed / Not in label — unassessed |
| Catheter site irritation | 49 · PRR 30.5 | 101 · PRR 141.4 | Not in label — unassessed / Not in label — unassessed |
| Vascular device occlusion | 44 · PRR 25.3 | 54 · PRR 58.2 | Not in label — unassessed / Not in label — unassessed |
| Catheter site vesicles | 45 · PRR 51.8 | 49 · PRR 104.9 | Not in label — unassessed / Not in label — unassessed |
| Ventilation perfusion mismatch | 46 · PRR 33.6 | 39 · PRR 49.9 | Not in label — unassessed / Not in label — unassessed |
| Catheterisation cardiac abnormal | 38 · PRR 27.6 | 44 · PRR 59.4 | Not in label — unassessed / Not in label — unassessed |
Labeled signals distinctive to Ambrisentan
- Infusion site oedema — n=109, PRR 25.5 Labeled (related wording)
Labeled signals distinctive to Macitentan
- Cardiac failure high output — n=56, PRR 93.7 Labeled (related wording)
Common questions
Which has more reported side effects, Ambrisentan or Macitentan?
Ambrisentan has 124,082 FAERS reports and Macitentan 68,750. More reports does not mean more dangerous: volume follows how widely and how long a drug has been used, prescription vs over-the-counter status, and publicity. The seriousness share (65% vs 71%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Ambrisentan and Macitentan share?
Both drugs carry disproportionality signals for right ventricular failure, infusion site infection, pulmonary veno-occlusive disease, pulmonary arterial hypertension, catheter site erythema. Shared signals often reflect a shared drug class or the condition both are used for.
Is Ambrisentan or Macitentan safer?
FAERS cannot answer that: it has no denominator and no comparator. Use this page to see which risks are already on each label and which signals are unlabeled, then check the prescribing information and your clinician for your situation.
Sources: openFDA FAERS pair statistics (OpenPV build 2026-09-14), FDA labels via openFDA, openFDA count queries for seriousness and deaths. Pair chosen because it is a commonly searched comparison. Generated 2026-10-08.