Protriptyline 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
Protriptyline
No brand names on record
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.
You've been prescribed buprenorphine (an opioid used for pain or opioid dependence) along with protriptyline (a tricyclic antidepressant). Both drugs can affect your heart's rhythm, both can raise levels of a brain chemical called serotonin, and both can slow down your gut. Taken together, these effects can add up.
This means there's a slightly higher chance of an irregular heartbeat, a condition called serotonin syndrome (which can cause agitation, shaking, sweating, or a fast heartbeat), and serious constipation. This concern is mostly theoretical, so try not to worry. Your care team can manage it by watching you closely, and they'll adjust things if needed. Just let them know about any new symptoms.
Additive toxicity risk when buprenorphine is combined with protriptyline. Neither agent's effect is prodrug-dependent here, so the risks are straightforwardly additive across three axes:
- QT prolongation: both agents can prolong the QT interval, raising torsades risk.
- Serotonin syndrome: additive serotonergic activity (buprenorphine has weak serotonergic effects; TCAs inhibit serotonin reuptake).
- GI motility: additive slowing may precipitate severe constipation or paralytic ileus.
Evidence: theoretical. Onset: unspecified. Management: avoid if possible; if co-prescribed, monitor closely during initiation and titration, consider ECG surveillance, watch for neuromuscular/autonomic signs, and monitor bowel function. Discontinue if serotonin syndrome is suspected.
What happens
An increased risk of QT interval prolongation, an increased risk of serotonin syndrome and an increased risk of paralytic ileus
Interaction Deep Dive
Buprenorphine should not be used together with medications that may prolong the QT interval34. In addition, combining buprenorphine with other drugs that act on the serotonergic neurotransmitter system can heighten the likelihood of serotonin syndrome. When such combined use cannot be avoided, monitor the patient, particularly at the start of therapy and when adjusting the dose, and stop treatment if serotonin syndrome is suspected. Watch for indications of severe constipation, as this may lead to paralytic ileus21.
Why it happens (mechanism)
Additive QT interval prolongation; additive serotonergic effects; additive effects on gastric motility
How to manage this interaction
Keep taking both medications exactly as prescribed and do not stop either one on your own. Your care team can manage this combination.
- Your prescriber may avoid this pairing if a good alternative exists, or watch you more closely if you need both.
- Doses may need to be adjusted and individualized, especially when starting or changing either drug.
- Tell your team right away about a fast or irregular heartbeat, fainting, agitation, shaking, sweating, fever, or confusion (possible serotonin syndrome).
- Report severe or worsening constipation, which can signal a bowel that has stopped moving.
Bring up any heart-rhythm history with your pharmacist or doctor.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Protriptyline and Buprenorphine together?
Combining buprenorphine and protriptyline can add up to raise the risk of heart-rhythm problems, serotonin syndrome, and severe constipation, so it's best avoided when possible. If you take both, stay on them as prescribed and let your care team monitor you and adjust doses. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Protriptyline 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 Protriptyline and Buprenorphine interaction managed?
Keep taking both medications exactly as prescribed and do not stop either one on your own. Your care team can manage this combination. Your prescriber may avoid this pairing if a good alternative exists, or watch you more closely if you need both. Doses may need to be adjusted and individualized, especially when starting or changing either drug. Tell your team right away about a fast or irregular… 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 Protriptyline 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 Protriptyline
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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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