Drug interactions
Buprenorphine + Phenobarbital
Severity: Major
Buprenorphine and Phenobarbital: major interaction.
Last updated Sources: US FDA label
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Phenobarbital and buprenorphine together increase the risk of profound sedation and respiratory depression. Phenobarbital also induces CYP3A4 and can lower buprenorphine exposure over time, risking withdrawal or loss of analgesia.
What this interaction means in plain words
Buprenorphine and Phenobarbital can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Additive CNS depression plus CYP3A4 induction by phenobarbital increasing buprenorphine clearance.
What to do
Avoid if possible; otherwise monitor sedation and respiration and titrate buprenorphine to effect. Reassess doses when phenobarbital is started or stopped.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
Other interactions of Buprenorphine
- Alvimopan + Buprenorphine Contraindicated
- Buprenorphine + Calcium / magnesium / potassium / sodium oxybates Contraindicated
- Buprenorphine + Olanzapine / samidorphan Contraindicated
- Buprenorphine + Phenelzine Contraindicated
- Buprenorphine + Pimozide Contraindicated
- Buprenorphine + Thioridazine Contraindicated
Frequently asked questions
Can I take Buprenorphine with Phenobarbital?
MediHelp rates the interaction as major. Buprenorphine and Phenobarbital can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Phenobarbital and buprenorphine together increase the risk of profound sedation and respiratory depression. Phenobarbital also induces CYP3A4 and can lower buprenorphine exposure over time, risking withdrawal or loss of analgesia.
How serious is the interaction between Buprenorphine and Phenobarbital?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid if possible; otherwise monitor sedation and respiration and titrate buprenorphine to effect. Reassess doses when phenobarbital is started or stopped.
What other medicines interact with Buprenorphine?
MediHelp also lists interactions of Buprenorphine with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Olanzapine / samidorphan. The full list is on the Buprenorphine page.
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