Drug Interaction Report

Buprenorphine and Osilodrostat: 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

Belbuca Brixadi Buprenex BuTrans Simbadol Sublocade Zorbium
+

Osilodrostat

Isturisa
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Updated Jul 2, 2026
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Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
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.

Of 633 documented Buprenorphine interactions, 601 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
At a glance + Theoretical Effects may be stronger
The Bottom Line
Buprenorphine and osilodrostat can each stretch the QT interval, so together they add up the risk of an irregular heartbeat; your care team can manage this with more frequent EKGs and by adjusting the osilodrostat dose. Keep taking both as prescribed and report any dizziness, fainting, or palpitations.

Both buprenorphine (a pain and addiction medicine) and osilodrostat (Isturisa, used for Cushing's disease) can affect your heart's rhythm. Each one can stretch out a part of your heartbeat called the QT interval. When you take them together, that effect can add up, which in rare cases can lead to an irregular heartbeat.

The good news is this is a known, manageable concern, not a reason to panic. Your care team may check your heart with an EKG more often and can adjust your osilodrostat dose if needed. Keep taking both medicines as prescribed, and let your doctor or pharmacist know if you feel dizzy, faint, or notice a fluttering heartbeat.

Additive QT prolongation. Both agents independently prolong the QTc interval; osilodrostat's effect is dose-dependent, and buprenorphine carries a recognized QT-prolonging signal. Concurrent use is a pharmacodynamic (additive) interaction, not a metabolic one. Neither drug's activity here depends on prodrug conversion.

  • Direction: increased combined QT prolongation risk.
  • Evidence: theoretical; severity rated major.
  • Onset: unspecified.
  • Management: use caution with concomitant use; obtain more frequent ECG monitoring; correct electrolytes (K+, Mg2+); consider temporary discontinuation of osilodrostat if QTc exceeds 480 ms. Individualize osilodrostat dosing.
Onset
unspecified
Evidence
theoretical
Severity
Major

What happens

Increased risk of QT interval prolongation

Interaction Deep Dive

Use osilodrostat cautiously when it is combined with other agents recognized for prolonging the QT interval, since osilodrostat itself produces a dose-dependent prolongation of the QT interval. When these drugs are given together, more frequent ECG monitoring may be warranted. Temporary withdrawal of osilodrostat should be considered should the QTc interval exceed 480 milliseconds1.

Why it happens (mechanism)

Additive QT interval prolongation

How to manage this interaction

This is manageable with monitoring. Keep taking both medicines exactly as prescribed unless your care team tells you otherwise. Because each can affect your heart rhythm, your team may:

  • Check your heart with an EKG more often, especially when starting or changing doses.
  • Adjust and individualize your osilodrostat dose, and temporarily pause it if your QTc reading gets too high (above 480 milliseconds).
  • Keep an eye on blood levels like potassium and magnesium.

Tell your pharmacist or prescriber about all other medicines you take, and report any dizziness, fainting, or palpitations right away.

Management is individual — confirm any change with your pharmacist or prescriber.

Common questions

Can I take Buprenorphine and Osilodrostat together?

Buprenorphine and osilodrostat can each stretch the QT interval, so together they add up the risk of an irregular heartbeat; your care team can manage this with more frequent EKGs and by adjusting the osilodrostat dose. Keep taking both as prescribed and report any dizziness, fainting, or palpitations. Always confirm with your pharmacist or prescriber before making any change.

How serious is the Buprenorphine and Osilodrostat 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 Osilodrostat interaction managed?

This is manageable with monitoring. Keep taking both medicines exactly as prescribed unless your care team tells you otherwise. Because each can affect your heart rhythm, your team may: Check your heart with an EKG more often, especially when starting or changing doses. Adjust and individualize your osilodrostat dose, and temporarily pause it if your QTc reading gets too high (above 480 millisecon… Management is individual — always follow your own care team's guidance.

How strong is the evidence for this interaction?

The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.

Questions for your pharmacist

  • Does my dose of Buprenorphine or Osilodrostat 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 (1)

  1. Product Information: ISTURISA(R) oral tablets, osilodrostat oral tablets. Recordati Rare Disease Inc (per FDA), Lebanon, NJ, 2020. DailyMed
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Beyond drug–drug

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.