Buprenorphine and Ciprofloxacin: 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
Ciprofloxacin
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.
Let's talk about taking buprenorphine (an opioid pain or addiction medicine) together with the antibiotic ciprofloxacin. Ciprofloxacin can slow down how your body breaks down buprenorphine, so more of it can build up in your blood. That may make the opioid effects stronger, including too much sleepiness or slowed breathing.
On top of that, both medicines can gently affect your heart's rhythm, so together they may raise the chance of a rhythm change called QT prolongation.
The good news is your care team can manage this. They may adjust your buprenorphine dose and watch you more closely. Keep taking both as prescribed, and reach out to your pharmacist or doctor with any questions.
Effect: Ciprofloxacin, a CYP3A4 inhibitor, can reduce buprenorphine metabolism, increasing buprenorphine exposure and risk of opioid adverse events (sedation, respiratory depression). Both agents independently prolong the QT interval, giving additive risk.
Direction: Increased buprenorphine effect. Neither drug relies on activation, so inhibition raises active drug levels.
- Severity: Major. Evidence: Probable. Onset: Unspecified.
- Monitor: ECG/QTc, sedation, respiratory rate.
- Manage: Consider reducing buprenorphine dose until stable; on cipro discontinuation, anticipate needing a dose increase and watch for withdrawal. Use formulations allowing precise titration when needed.
What happens
An increased risk of QT interval prolongation, increased buprenorphine exposure and an increased risk of buprenorphine-related adverse events
Interaction Deep Dive
Because a CYP3A4 inhibitor can raise buprenorphine plasma concentrations, using it together with buprenorphine may result in extended opioid effects, such as respiratory depression. The concurrent use of agents that influence cardiac conduction also raises the likelihood of QT prolongation. When these drugs are given together, watch the patient carefully for any lengthening of the QT interval. It may be appropriate to lower the buprenorphine dose until steady drug effects are reached, while checking often for sedation and respiratory depression. If a CYP3A4 inhibitor is stopped in someone already taking buprenorphine, consider raising the buprenorphine dose until stable effects are attained, and observe for indications of opioid withdrawal2. Should dose adjustment not be feasible once the CYP3A4 inhibitor is gone, switch the patient back to a buprenorphine formulation that allows finer dose titration. For patients moving from transmucosal buprenorphine taken with CYP3A4 inhibitors, confirm that the plasma buprenorphine level delivered by subQ buprenorphine is sufficient. For those already receiving subQ buprenorphine who then need a CYP3A4 inhibitor, watch for indications of over-medication. If features of buprenorphine toxicity or overdose develop and the accompanying drug cannot be lowered or stopped, decrease the buprenorphine dose. When the available doses cannot deliver the intended dose, stop treatment and manage the patient with a buprenorphine formulation that allows more precise dose adjustments 1.
Why it happens (mechanism)
Additive QT interval prolongation; inhibition of CYP3A4-mediated metabolism of buprenorphine
How to manage this interaction
Both drugs can be used together safely with attention from your care team. Here is what they typically do:
- Closer monitoring for excess sleepiness, slowed breathing, and heart rhythm (an ECG may be checked).
- Your buprenorphine dose may need to be adjusted and individualized until your response is steady.
- When the antibiotic is stopped, your team may raise the buprenorphine dose again and watch for withdrawal signs.
What you should do: Keep taking both exactly as prescribed. Do not change doses yourself. Tell your pharmacist or prescriber about severe drowsiness, trouble breathing, fainting, or palpitations.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) In a study of healthy volunteers (N=12), giving oral buprenorphine together with voriconazole produced a significant increase in the mean AUC(0 to 18 hours) of buprenorphine, rising 4.3-fold (from 0.43 to 2.1 nanograms (ng) x hr/mL), along with a 3.9-fold rise in Cmax (from 0.057 to 0.22 ng/mL), a longer half-life (from 9.1 to 14.5 hours), and greater urinary clearance (from 0.31 to 0.73 L/hr). Voriconazole likewise significantly raised exposure to the active metabolite norbuprenorphine, by nearly 4-fold for AUC(0 to 18 hours) and by 3.3-fold for Cmax, while lowering its renal clearance (from 7.2 to 2.9 L/hr). Participants reported mild dizziness and nausea in both phases. Subjects were given either placebo or voriconazole 400 mg twice daily on day 1, then 200 mg twice daily on days 2 to 5, followed by a 4-week washout before crossing over to the alternate regimen. On the fifth day, every subject received a single oral dose of buprenorphine 0.2 mg, or 3.6 mg during the placebo phase 3.
b) The impact of concurrently administered CYP3A4 inhibitors on buprenorphine exposure in patients receiving subQ buprenorphine has not been investigated; nevertheless, such interactions have been demonstrated in studies employing transmucosal buprenorphine. The effects of buprenorphine may vary according to the route of administration 1.
Common questions
Can I take Buprenorphine and Ciprofloxacin together?
Ciprofloxacin can raise buprenorphine levels and both can affect heart rhythm, so watch for excess sedation, slowed breathing, and QT changes. Keep taking both as prescribed and let your care team adjust and monitor. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Buprenorphine and Ciprofloxacin 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 Ciprofloxacin interaction managed?
Both drugs can be used together safely with attention from your care team. Here is what they typically do: Closer monitoring for excess sleepiness, slowed breathing, and heart rhythm (an ECG may be checked). Your buprenorphine dose may need to be adjusted and individualized until your response is steady. When the antibiotic is stopped, your team may raise the buprenorphine dose again and watch for… 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 Ciprofloxacin 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: ZUBSOLV(R) sublingual tablets, buprenorphine naloxone sublingual tablets. Orexo US Inc (per FDA), Morristown, NJ, 2023. DailyMed
- Fihlman M, Hemmila T, Hagelberg NM, et al: Voriconazole greatly increases the exposure to oral buprenorphine. Eur J Clin Pharmacol 2018; 74(12):1615-1622. PubMed
Keep reading about Buprenorphine
Keep reading about Ciprofloxacin
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