Buprenorphine and Ivacaftor: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Buprenorphine
Ivacaftor
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.
Here is what is going on. Your body uses a liver enzyme called CYP3A4 to break down buprenorphine (your opioid pain or addiction medicine). Ivacaftor (Kalydeco) can slow that enzyme down a bit. When the enzyme works slower, buprenorphine can build up in your blood and its effects last longer.
That matters because too much buprenorphine can make you very sleepy or slow your breathing. Watch for unusual drowsiness, confusion, or slow or shallow breathing. Please do not stop or change either medicine on your own. Your care team can manage this safely by adjusting your dose and keeping a closer eye on you, so let your pharmacist or doctor know you take both.
Mechanism: Ivacaftor is a weak CYP3A4 inhibitor; buprenorphine is a CYP3A4 substrate (active drug, not a prodrug). Inhibition reduces buprenorphine metabolism, increasing plasma concentrations and AUC.
Effect: Increased buprenorphine exposure with risk of prolonged opioid effects, including sedation and respiratory depression. Evidence: probable; onset unspecified; severity major.
Management:
- If starting ivacaftor, consider reducing buprenorphine dose until stable; monitor for sedation/respiratory depression.
- On discontinuing ivacaftor, consider increasing buprenorphine; monitor for withdrawal.
- For long-acting subQ formulations, consider transition to a formulation allowing precise titration if adjustment is needed.
What happens
Increased buprenorphine exposure and an increased risk of buprenorphine-related adverse events
Interaction Deep Dive
Combining buprenorphine with a CYP3A4 inhibitor can raise buprenorphine plasma concentrations, which may lead to extended opioid effects such as respiratory depression. When a patient on buprenorphine must also receive a CYP3A4 inhibitor, consider lowering the buprenorphine dose until stable drug effects are reached, along with frequent monitoring for sedation and respiratory depression. Conversely, if a CYP3A4 inhibitor is stopped in someone taking buprenorphine, consider raising the buprenorphine dose until stable drug effects are attained, and watch for signs of opioid withdrawal2. Should dose adjustment prove impossible once the CYP3A4 inhibitor is gone, switch the patient back to a buprenorphine formulation that allows finer dose titration. For patients transitioned from transmucosal buprenorphine given together with CYP3A4 inhibitors, confirm through monitoring that the plasma buprenorphine level delivered by subQ buprenorphine is sufficient. For those already receiving subQ buprenorphine who then need a CYP3A4 inhibitor, monitor for signs and symptoms of over-medication. If buprenorphine toxicity or overdose signs and symptoms develop and the concomitant drug cannot be lowered or stopped, decrease the buprenorphine dose. When the available doses do not allow the target dose to be reached, stop the treatment and manage the patient with a buprenorphine formulation that permits more precise dose adjustments 1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of buprenorphine
How to manage this interaction
Keep taking both medicines as prescribed unless your care team tells you otherwise. This combination is manageable with the right dosing and monitoring.
- Your team may lower your buprenorphine dose while you are on ivacaftor, then adjust it back up if ivacaftor is stopped. The dose may need to be individualized by your care team.
- Expect closer monitoring for over-sedation and slow breathing when starting, and for withdrawal signs when stopping ivacaftor.
- If you use a long-acting injectable buprenorphine, your team may switch you to a form that is easier to fine-tune.
Call your pharmacist or prescriber if you feel unusually drowsy, confused, or notice slow or shallow breathing.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) The impact of concurrently administered CYP3A4 inhibitors on buprenorphine exposure in individuals receiving subQ buprenorphine has not been examined; nevertheless, these interactions have been demonstrated in investigations that used transmucosal buprenorphine. Buprenorphine's effects may vary according to the route by which it is administered 1.
Common questions
Can I take Buprenorphine and Ivacaftor together?
Ivacaftor can raise buprenorphine levels and increase the risk of sedation and slowed breathing, so keep taking both as prescribed but tell your care team, who can adjust your buprenorphine dose and monitor you more closely. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Buprenorphine and Ivacaftor 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 is the Buprenorphine and Ivacaftor interaction managed?
Keep taking both medicines as prescribed unless your care team tells you otherwise. This combination is manageable with the right dosing and monitoring. Your team may lower your buprenorphine dose while you are on ivacaftor, then adjust it back up if ivacaftor is stopped. The dose may need to be individualized by your care team. Expect closer monitoring for over-sedation and slow breathing when st… Management is individual — always follow your own care team's guidance.
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 Buprenorphine or Ivacaftor 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: BRIXADI(TM) subcutaneous extended-release injection, buprenorphine subcutaneous extended-release injection. Braeburn Inc (per FDA), Plymouth Meeting, PA, 2023. DailyMed
- Product Information: ZUBSOLV(R) sublingual tablets, buprenorphine naloxone sublingual tablets. Orexo US Inc (per FDA), Morristown, NJ, 2023. DailyMed
Keep reading about Buprenorphine
Keep reading about Ivacaftor
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