Buprenorphine and Trazodone: 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
Trazodone
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.
Buprenorphine (like Belbuca or Suboxone) and trazodone can affect your body in three overlapping ways when taken together. Both can slow down your brain and breathing, so you may feel extra sleepy, dizzy, or foggy. Both can also nudge up serotonin, a brain chemical, and rarely that can cause a serious reaction called serotonin syndrome (agitation, shaking, sweating, fast heartbeat). And both can affect your heart's rhythm.
Right now this warning is mostly theoretical, based on how the drugs work rather than lots of reports. Please do not stop either one on your own. Talk with your pharmacist or doctor, who can adjust things and keep a close eye on you.
Mechanism: additive effects across three domains, additive QT prolongation, additive serotonergic activity, and additive CNS/respiratory depression. Neither agent is dependent on prodrug activation for this interaction; both contribute directly.
- Direction: increased risk of arrhythmia (QTc), serotonin syndrome, and CNS depression.
- Onset: unspecified; serotonin syndrome risk highest at initiation/dose escalation.
- Evidence: theoretical; severity rated major.
- Management: avoid combination if possible. If required, counsel patient, monitor for sedation, respiratory depression, and serotonin syndrome (mental status change, autonomic instability, neuromuscular findings). Consider ECG in patients with QT risk factors. Discontinue and provide supportive care if serotonin syndrome develops.
What happens
Increased risk of QT interval prolongation, an increased risk of serotonin syndrome and an increased risk of CNS depression
Interaction Deep Dive
Do not give traZODone together with CNS depressants that possess serotonergic activity and are recognized for prolonging the QT interval, since doing so can heighten the likelihood of cardiac arrhythmia1 as well as raise the potential for CNS depression. Advise patients that traZODone can amplify their reaction to CNS depressants. Furthermore, using traZODone alongside other serotonergic medications may cause serotonin syndrome, a condition that can be life-threatening. Its signs and symptoms may encompass altered mental status (for example, agitation, hallucinations, delirium, coma), autonomic instability (for example, tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular manifestations (for example, tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, and gastrointestinal effects like nausea, vomiting, or diarrhea. Every patient receiving traZODone therapy should be watched for serotonin syndrome, particularly when treatment is being started. When concurrent use cannot be avoided, inform patients about the elevated risk of serotonin syndrome and observe them for symptoms. Should symptoms develop, promptly stop traZODone and any accompanying serotonergic agent and begin supportive care 2.
Why it happens (mechanism)
Additive QT interval prolongation; additive serotonergic effects; additive CNS depression
How to manage this interaction
Your care team may prefer to avoid using these two together, but if both are needed they can manage it safely.
- Keep taking both as prescribed unless your prescriber tells you otherwise.
- Doses may need to be individualized, and your team may monitor you more closely, especially when either drug is started or increased.
- Watch for heavy drowsiness, slow or shallow breathing, confusion, fast heartbeat, tremor, sweating, fever, or agitation.
- Get urgent help if these appear, and tell your pharmacist and doctor about all your medicines, including anything new.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Buprenorphine and Trazodone together?
Combining buprenorphine and trazodone adds up risks of excess sedation/slowed breathing, heart rhythm changes, and rarely serotonin syndrome, so avoid it if possible and let your care team adjust doses and monitor you closely if both are needed. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Buprenorphine and Trazodone 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 Trazodone interaction managed?
Your care team may prefer to avoid using these two together, but if both are needed they can manage it safely. Keep taking both as prescribed unless your prescriber tells you otherwise. Doses may need to be individualized, and your team may monitor you more closely, especially when either drug is started or increased. Watch for heavy drowsiness, slow or shallow breathing, confusion, fast heartbeat… 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.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Buprenorphine or Trazodone 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)
Keep reading about Buprenorphine
Keep reading about Trazodone
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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