Carbachol 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
Carbachol
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 is a strong pain and opioid-treatment medicine that can make you feel drowsy, relaxed, and slow your breathing a little. Carbachol is usually given as an eye drop or during eye surgery, but in theory it may add to that same sleepy, calming effect on your nervous system.
Put together, you might feel more tired, dizzy, or foggy than usual. The good news is this concern is mostly theoretical, meaning it hasn't been clearly shown to cause big problems in real life. Your care team can easily keep an eye on how you feel and adjust things if needed, so let your pharmacist or doctor know you take both.
Effect: Theoretical additive CNS depression when carbachol is combined with buprenorphine (an opioid partial agonist with sedative and respiratory-depressant properties).
- Mechanism: Additive pharmacodynamic CNS depression; not a PK/enzyme interaction. Neither agent is metabolically dependent for activation.
- Direction: Increased sedation/CNS depressant effect.
- Magnitude/onset: Unspecified; evidence is theoretical, and systemic carbachol exposure from ophthalmic use is typically minimal.
- Management: Monitor for excess sedation, dizziness, and respiratory depression. Dose may be individualized; no fixed adjustment defined.
What happens
An increased risk of CNS depression
Interaction Deep Dive
When carbachol is given together with CNS depressants, the resulting CNS effects may be additive1.
Why it happens (mechanism)
Additive CNS depression
How to manage this interaction
Keep taking both medicines exactly as prescribed unless your care team tells you otherwise. This is a theoretical caution, so the practical focus is watching how you feel.
- Watch for extra drowsiness, dizziness, confusion, or slowed breathing, especially when starting either medicine.
- Tell your team that you use both buprenorphine and carbachol so they can monitor you more closely.
- Your dose may be adjusted and individualized by your care team if you notice too much sedation.
- Do not stop or change either medicine on your own; check with your pharmacist or prescriber first.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Carbachol and Buprenorphine together?
Combining buprenorphine with carbachol carries a theoretical risk of added drowsiness or slowed breathing; keep taking both as prescribed and tell your pharmacist or doctor so they can watch for extra sedation. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Carbachol and Buprenorphine interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Carbachol and Buprenorphine interaction managed?
Keep taking both medicines exactly as prescribed unless your care team tells you otherwise. This is a theoretical caution, so the practical focus is watching how you feel. Watch for extra drowsiness, dizziness, confusion, or slowed breathing, especially when starting either medicine. Tell your team that you use both buprenorphine and carbachol so they can monitor you more closely. Your dose may be… 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 Carbachol 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 anything you'd monitor while I'm on both?
References (1)
- Product Information: YUVEZZI™ ophthalmic solution, carbachol brimonidine tartrate 2.75%/0.1% ophthalmic solution. Visus Therapeutics Inc. (per FDA), Seattle, WA, 2026. DailyMed
Keep reading about Buprenorphine
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major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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