Ivacaftor and Macitentan: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ivacaftor
Macitentan
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Reduced macitentan exposure
Interaction Deep Dive
Avoid concomitant use of macitentan with strong CYP3A4 inducers, as coadministration significantly reduces macitentan exposure12. In a pharmacokinetic study, concomitant treatment with rifampicin 600 mg daily, a potent inducer of CYP3A4, reduced the steady-state exposure to macitentan by 79% but did not affect the exposure to the active metabolite 2.
Why it happens (mechanism)
Induction of CYP3A4-mediated metabolism of macitentan
Literature reports
1 report — tap to read
a) In a pharmacokinetic study, concomitant treatment with rifampicin 600 mg daily, a potent inducer of CYP3A4, reduced the steady-state exposure to macitentan by 79% but did not affect the exposure to the active metabolite 2.
Common questions
Can I take Ivacaftor and Macitentan together?
Reduced macitentan exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ivacaftor and Macitentan interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Ivacaftor or Macitentan need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (2)
- Product Information: OPSUMIT(R) oral tablets, macitentan oral tablets. Actelion Pharmaceuticals US Inc (per FDA), Titusville, NJ, 2023. DailyMed
- Product Information: OPSYNVI(R) oral tablets, macitentan tadalafil oral tablets. Actelion Pharmaceuticals US, Inc. (Per FDA), Titusville, NJ, 2024. DailyMed
Keep reading about Ivacaftor
Keep reading about Macitentan
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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