Quinidine and Buprenorphine: 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
Quinidine
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.
Both buprenorphine (a pain and addiction medicine) and quinidine (a heart rhythm medicine) can affect the heart's electrical timing, something called the QT interval. When two medicines that each do this are taken together, the effect can add up and, in some people, raise the risk of an irregular heartbeat.
The good news is that this is a known concern your care team can plan around. They may check your heart rhythm with an EKG, watch your potassium and magnesium levels, and tailor your treatment to you. Please don't stop or change either medicine on your own. Talk with your doctor or pharmacist about the safest option.
Effect: Additive risk of QT interval prolongation with concomitant buprenorphine and quinidine (a class Ia antiarrhythmic and well-recognized QT-prolonging agent).
- Mechanism: Additive pharmacodynamic effect on cardiac repolarization; neither drug is a prodrug, so effect direction is additive, not altered by activation.
- Severity: Major. Evidence: Theoretical. Onset: Unspecified.
- Management: Avoid combination where possible. If used, obtain baseline and follow-up ECG, correct/monitor potassium and magnesium, and assess additional risk factors (bradycardia, CHF, congenital long-QT, recent AF conversion, digoxin therapy).
What happens
An increased risk of QT interval prolongation
Interaction Deep Dive
Do not use buprenorphine together with medications capable of prolonging the QT interval342. It remains unknown what risk arises when buprenorphine is paired with other agents that prolong QT. When prescribing buprenorphine to patients who have risk factors, these observations should factor into clinical decisions; such risk factors include hypokalemia, bradycardia, recent conversion from atrial fibrillation, congestive heart failure, digitalis therapy, baseline QT prolongation, subclinical long-QT syndrome, or severe hypomagnesemia 1.
Why it happens (mechanism)
Additive QT interval prolongation
How to manage this interaction
Your care team can manage this combination carefully if you need both drugs:
- They may avoid using them together when a safer alternative exists.
- They may check your heart rhythm with an EKG and monitor your potassium and magnesium levels.
- They will consider added risk factors such as a slow heart rate, heart failure, or a known long-QT history.
What you can do: Keep taking both exactly as prescribed unless told otherwise, and ask your pharmacist or doctor whether this pairing is right for you. Report any fainting, dizziness, or palpitations promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Quinidine and Buprenorphine together?
Combining buprenorphine and quinidine can add together to prolong the QT interval, so this pairing is best avoided or closely monitored. Ask your care team before making any changes. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Quinidine and Buprenorphine 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 Quinidine and Buprenorphine interaction managed?
Your care team can manage this combination carefully if you need both drugs: They may avoid using them together when a safer alternative exists. They may check your heart rhythm with an EKG and monitor your potassium and magnesium levels. They will consider added risk factors such as a slow heart rate, heart failure, or a known long-QT history. What you can do: Keep taking both exactly as prescrib… 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 Quinidine or Buprenorphine 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 (4)
- Product Information: BRIXADI(TM) subcutaneous extended-release injection, buprenorphine subcutaneous extended-release injection. Braeburn Inc (per FDA), Plymouth Meeting, PA, 2023. DailyMed
- Product Information: BUTRANS(R) transdermal system patch, buprenorphine transdermal system patch. Purdue Pharma L.P. (per FDA), Stamford, CT, 2016. DailyMed
- Product Information: BELBUCA(TM) buccal film, buprenorphine buccal film. Endo Pharmaceuticals Inc. (per FDA), Malvern, PA, 2016.
- Product Information: BUPRENEX(R) intravenous injection, intramuscular injection, buprenorphine HCl intravenous injection, intramuscular injection. Indivior Inc. (per DailyMed), Richmond, VA, 2016. DailyMed
Keep reading about Buprenorphine
Keep reading about Quinidine
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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