Buprenorphine and Buspirone: 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
Buspirone
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.
Taking buprenorphine with buspirone can add up in two ways. Buprenorphine is a strong pain and opioid-treatment medicine that can slow your breathing and make you very sleepy. Buspirone works on serotonin, a brain chemical. When you take both, they can make each other's effects stronger.
Two things to watch for: too much drowsiness or slowed breathing, and a rare reaction called serotonin syndrome (things like shaking, a racing heart, sweating, agitation, or confusion). The good news is your care team can manage this. Keep taking both exactly as prescribed, and tell your pharmacist or doctor if you feel unusually sleepy, foggy, or jittery.
Interaction: Additive risk of serotonin syndrome plus additive CNS and respiratory depression. Buprenorphine (partial mu-opioid agonist) contributes sedation and respiratory depression; buspirone contributes serotonergic activity. Neither is a relevant prodrug here; the effect is pharmacodynamic (PD), not PK.
- Direction: increased combined effect (sedation, respiratory depression, serotonin toxicity).
- Severity/evidence: major; probable substantiation. Onset unspecified.
- Management: avoid or minimize concomitant CNS depressants; use lowest effective doses. Monitor for sedation, respiratory depression, and serotonin syndrome, especially at initiation and dose changes. Discontinue buprenorphine if serotonin syndrome is suspected and consider alternative anxiety therapy.
What happens
An increased risk of serotonin syndrome and an increased risk of respiratory and CNS depression
Interaction Deep Dive
When buprenorphine is given together with a serotonergic CNS depressant, the effects on the CNS can be additive, raising the likelihood of serotonin syndrome as well as respiratory depression, deep sedation, coma, and death. Rather than using these agents together, discontinuing the other CNS depressant is the favored approach. Depending on the situation, it may be suitable to monitor the patient at a higher level of care or to pursue a taper. In other circumstances, slowly weaning a patient off a prescribed benzodiazepine or another CNS depressant, or reducing to the lowest dose that remains effective, may be suitable. Should combined use be required, watch for sedation, respiratory depression, and the signs and symptoms of serotonin syndrome. Observe the patient closely, especially when therapy is being started and when the dose of the serotonergic agent is being adjusted. If serotonin syndrome is suspected, stop buprenorphine and consider alternative approaches for managing anxiety or insomnia21.
Why it happens (mechanism)
Additive serotonergic effects; additive CNS and respiratory depression
How to manage this interaction
Keep taking both as prescribed unless your prescriber tells you otherwise. Your care team can manage this combination.
- Your doses may be adjusted and individualized, often using the lowest effective dose of each.
- Your team may monitor you more closely, especially when starting or changing the buspirone dose.
- Ask whether a different anxiety option might be a better fit for you.
Call your pharmacist or doctor right away if you notice heavy drowsiness, confusion, slowed or shallow breathing, or signs of serotonin syndrome such as agitation, shivering, sweating, fast heartbeat, or muscle twitching.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) A Swedish epidemiological study reported that patients on methadone- or buprenorphine-based medication-assisted treatment (MAT) taken together with benzodiazepines or other CNS depressants (for example, medications used for insomnia) have an increased risk of death. Among MAT-prescribed patients (aged 18 to 50), the risk of fatal overdose, non-overdose related mortality, and all-cause mortality was analyzed by comparing periods when CNS depressants were prescribed with periods without CNS depressant therapy, between July 1, 2005 and 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 MAT and benzodiazepine treatment; however, these data were not regarded as statistically significant. Although the results showed a raised risk of fatal overdose, non-overdose mortality, and all-cause mortality during periods of coadministration of MAT and non-benzodiazepines, only the data for fatal overdose and all-cause mortality were regarded as statistically significant; HR 2.34 (95% CI, 1.37 to 3.99) and HR 1.33 (95% CI, 1.12 to 2.45), respectively. A comparison between the benzodiazepine cohort and the non-benzodiazepine cohort was not performed because the authors did not adjust for the indication of use for the drugs 3.
b) According to a study of aggregate nationwide death certificate data spanning 2010 to 2014, 3495 drug overdose deaths were reported in 2014. Methadone and other CNS depressants were frequently identified as contributors to those deaths. Concurrent alprazolam use was reported 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 involving buprenorphine. Of 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 the number of buprenorphine-involved deaths, though confounding factors and differences in drug utilization were not taken into account. It remains unknown whether the risk of overdose death with concomitant CNS depressant drugs differed between buprenorphine and methadone 3.
Common questions
Can I take Buprenorphine and Buspirone together?
Combining buprenorphine and buspirone can add up to cause excess sedation, slowed breathing, and a rare risk of serotonin syndrome, so keep taking both as prescribed and report severe drowsiness or agitation to your care team. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Buprenorphine and Buspirone 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 Buspirone interaction managed?
Keep taking both as prescribed unless your prescriber tells you otherwise. Your care team can manage this combination. Your doses may be adjusted and individualized, often using the lowest effective dose of each. Your team may monitor you more closely, especially when starting or changing the buspirone dose. Ask whether a different anxiety option might be a better fit for you. Call your pharmacist… 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.
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 Buspirone 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 Buspirone
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