Halothane 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
Halothane
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.
Buprenorphine (a strong pain and addiction-treatment medicine) and halothane (an older anesthesia gas used to put people to sleep for surgery) both slow down your brain and your breathing. When they are used together, those effects can add up. That can lead to very heavy sedation, dangerously slow or shallow breathing, and in serious cases it can become life-threatening.
The good news is that this is a well-known combination, and your care team plans for it. If you ever need surgery, your anesthesia and surgical teams will know you take buprenorphine and will watch your breathing closely. Always tell every doctor and your pharmacist about your buprenorphine before any procedure.
Mechanism: additive CNS and respiratory depression. Buprenorphine is a partial mu-opioid agonist; halothane is a volatile general anesthetic with intrinsic CNS-depressant properties. Neither is a prodrug here, so the effect is pharmacodynamic (additive), not metabolic.
- Direction: increased depressant effect (respiratory depression, profound sedation, coma, death).
- Severity/evidence: major; probable. Onset unspecified.
- Management: reserve concomitant use for monitored settings; anesthesia dosing should be individualized and titrated by the care team. Monitor respiratory rate, oxygenation, and sedation depth; ensure airway and reversal capability. Do not withhold buprenorphine-based MAT solely due to this interaction.
What happens
An increased risk of respiratory depression and CNS depression
Interaction Deep Dive
When buprenorphine is given together with a CNS depressant, the combined effect on the central nervous system may be additive, raising the likelihood of respiratory depression, deep sedation, coma, and death. Discontinuing CNS depressants is favored rather than using them concurrently. For certain patients, it may be suitable to observe them under a higher level of care or to implement a taper. For others, a suitable approach may involve slowly weaning the patient off a prescribed CNS depressant or reducing to the lowest dose that remains effective. Should concurrent use be required, exercise cautious monitoring and management; alternative treatments for anxiety or insomnia should be considered2. A Swedish epidemiological study found that patients undergoing methadone- or buprenorphine-based medication-assisted treatment (MAT) who also took benzodiazepines or other CNS depressants (for instance, medications used for insomnia) have an elevated risk of death. Data from nationwide death certificates aggregated over 2010 to 2014 showed that most overdose deaths involving buprenorphine and methadone also involved concurrent CNS depressant use. Whether the risk of fatal overdose from concurrent CNS depressant drugs varied between buprenorphine and methadone remains unknown 3.
Why it happens (mechanism)
Additive CNS depression
How to manage this interaction
This combination is usually only relevant around surgery, and it is managed by the team giving your anesthesia.
- Keep taking buprenorphine as prescribed unless your prescriber tells you otherwise. Do not stop it on your own before a procedure.
- Tell your surgeon, anesthesiologist, and pharmacist that you take buprenorphine, including the dose and form.
- Your care team may adjust and individualize your anesthesia dose and monitor you more closely for slowed breathing and deep sedation.
- If you also take other calming medicines (for sleep or anxiety), mention those too, since they add to the same effect.
Raise any concerns with your prescriber or pharmacist before surgery.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) A Swedish epidemiological study found that patients on methadone- or buprenorphine-based medication-assisted treatment (MAT) together with benzodiazepines or other CNS depressants (for example, medications used to treat insomnia) have an increased risk of death. Among MAT-treated patients (aged 18 to 50), researchers compared the risk of fatal overdose, non-overdose related mortality, and all-cause mortality during periods when CNS depressants were prescribed versus periods without CNS depressant therapy, over the interval from July 1, 2005 to December 31, 2012. The findings showed a raised risk of all-cause mortality (adjusted hazard ratio (HR) 1.44; 95% CI, 0.93 to 2.23) and non-overdose related mortality (HR 1.74; 95% CI 1.00 to 3.01) with combined MAT and benzodiazepine treatment; however, these data were not deemed statistically significant. Although the results also indicated a raised risk of fatal overdose, non-overdose mortality, and all-cause mortality during periods of coadministration of MAT and non-benzodiazepines, only the fatal overdose and all-cause mortality data reached statistical significance; HR 2.34 (95% CI, 1.37 to 3.99) and HR 1.33 (95% CI, 1.12 to 2.45), respectively. The authors did not compare the benzodiazepine cohort with the non-benzodiazepine cohort because they did not adjust for the indication for which the drugs were used 3.
b) According to a study of pooled nationwide death certificate data from 2010 to 2014, 3495 drug overdose deaths were reported in 2014. Methadone and other CNS depressants were commonly cited as contributors to those deaths. Concurrent ALPRAZolam use appeared in 18.1% of cases, followed by oxyCODONE (10.1%), cocaine (9.6%), heroin (9%), and diazePAM (6.6%). The FDA reported 322 drug overdose deaths in 2014 that involved buprenorphine. Among these 322 deaths, 32.9% involved ALPRAZolam, 17.4% involved clonazePAM, 11.2% involved diazePAM, 11.2% involved heroin, and 9.9% involved fentaNYL. The absolute number of methadone-involved deaths was 10 times that of buprenorphine-involved deaths, though confounding factors and differences in drug utilization were not taken into account. Whether the risk of overdose death with concomitant CNS depressant drugs differed between buprenorphine and methadone is unknown 3.
Common questions
Can I take Halothane and Buprenorphine together?
Buprenorphine and halothane both depress breathing and the brain, so together they raise the risk of dangerous sedation and slowed breathing. Make sure your surgical and anesthesia teams know you take buprenorphine so they can monitor and adjust care. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Halothane 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 Halothane and Buprenorphine interaction managed?
This combination is usually only relevant around surgery, and it is managed by the team giving your anesthesia. Keep taking buprenorphine as prescribed unless your prescriber tells you otherwise. Do not stop it on your own before a procedure. Tell your surgeon, anesthesiologist, and pharmacist that you take buprenorphine, including the dose and form. Your care team may adjust and individualize you… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Halothane 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 (3)
- Product Information: BRIXADI(TM) subcutaneous extended-release injection, buprenorphine subcutaneous extended-release injection. Braeburn Inc (per FDA), Plymouth Meeting, PA, 2023. DailyMed
- Product Information: SUBUTEX(R) sublingual tablets, buprenorphine sublingual tablets. Indivior Inc (per FDA), North Chesterfield, VA, 2021. DailyMed
- US Food and Drug Administration (FDA): Drug Safety Communications: FDA urges caution about withholding opioid addiction medications from patients taking benzodiazepines or CNS depressants: careful medication management can reduce risks. US Food and Drug Administration (FDA). Silver Spring, MD. 2017.
Keep reading about Buprenorphine
Keep reading about Halothane
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