Buprenorphine and Carisoprodol: 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
Carisoprodol
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.
Both of these medicines calm down your body and brain. Buprenorphine is an opioid used for pain or opioid use disorder, and carisoprodol (Soma) is a muscle relaxer. Taken together, they can add up and slow your breathing too much, make you very drowsy, and cause problems like severe constipation or trouble urinating.
This is a serious combination, but it does not mean you have to choose one over the other. Never stop either medicine on your own. Your care team can manage this safely by adjusting doses, watching you more closely, and sometimes providing naloxone as a safety net. Please talk with your pharmacist or doctor about the best plan for you.
Mechanism: additive CNS and respiratory depression from buprenorphine (partial mu-opioid agonist) plus carisoprodol (centrally acting muscle relaxant with sedating metabolite meprobamate); additive anticholinergic and opioid effects on gastric motility. Neither is a prodrug relevant to this interaction; effect is pharmacodynamic.
- Direction: enhanced sedation, respiratory depression, and reduced GI/bladder motility (urinary retention, severe constipation, possible paralytic ileus).
- Severity/evidence: major; probable. Registry data link buprenorphine plus CNS depressants to increased overdose death.
- Management: monitor respiratory status, sedation, bowel/bladder function; decrease muscle relaxant dose as needed; consider prescribing naloxone. Do not withhold MAT.
What happens
Enhanced neuromuscular blocking action, an increased risk of respiratory depression and CNS depression and an increased risk of paralytic ileus
Interaction Deep Dive
When buprenorphine is given together with anticholinergic drugs that are also skeletal muscle relaxants, the neuromuscular blocking effect of the muscle relaxants may be intensified, leading to a greater degree of respiratory depression, and it may additionally provoke urinary retention or severe constipation that can progress to paralytic ileus. During concurrent use, watch patients for indications of urinary retention, decreased gastric motility, or respiratory depression that could exceed what would ordinarily be anticipated. Reduce the muscle relaxant dose where appropriate and consider prescribing naloxone for the emergency management of opioid overdose1. A Swedish epidemiological study found that patients undergoing methadone- or buprenorphine-based medication-assisted treatment (MAT) in combination with benzodiazepines or other CNS depressants (for instance, agents used to treat insomnia) face an elevated risk of death. Based on an analysis of aggregate nationwide death certificate data spanning 2010 to 2014, most overdose deaths involving buprenorphine and methadone also involved concurrent CNS depressant use. Whether the risk of overdose death with concomitant CNS depressant drugs was different for buprenorphine versus methadone remains unknown 2.
Why it happens (mechanism)
Additive CNS depression; additive effects on gastric motility
How to manage this interaction
Keep taking both medicines exactly as prescribed unless your prescriber tells you otherwise. This combination can be managed safely with the right precautions.
- Your care team may adjust and individualize the muscle relaxant dose and monitor you more closely.
- Your prescriber may offer naloxone to keep at home as an emergency safety measure.
- Watch for and report slow or shallow breathing, extreme drowsiness, confusion, trouble urinating, or severe constipation/bloating.
- Avoid alcohol and other sedating medicines unless cleared by your team.
If you are on buprenorphine for opioid use disorder, do not stop it. Instead, raise any concerns with your pharmacist or prescriber.
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 for insomnia) have an increased risk of death. From July 1, 2005 through December 31, 2012, 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 among MAT-prescribed patients (aged 18 to 50). 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 deemed statistically significant. Although the results showed a heightened 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 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 of use of the drugs 2.
b) According to a study using aggregate nationwide death certificate data from 2010 to 2014, 3495 drug overdose deaths were reported in 2014. Methadone and other CNS depressants were often reported 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 remains unknown 2.
Common questions
Can I take Buprenorphine and Carisoprodol together?
Combining buprenorphine and carisoprodol adds up to dangerous drowsiness, slowed breathing, and gut problems, so use both only under close medical supervision and never adjust either dose on your own. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Buprenorphine and Carisoprodol 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 Carisoprodol interaction managed?
Keep taking both medicines exactly as prescribed unless your prescriber tells you otherwise. This combination can be managed safely with the right precautions. Your care team may adjust and individualize the muscle relaxant dose and monitor you more closely. Your prescriber may offer naloxone to keep at home as an emergency safety measure. Watch for and report slow or shallow breathing, extreme dr… 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 Buprenorphine or Carisoprodol 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)
- Product Information: BRIXADI(TM) subcutaneous extended-release injection, buprenorphine subcutaneous extended-release injection. Braeburn Inc (per FDA), Plymouth Meeting, PA, 2023. 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 Carisoprodol
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