Buprenorphine and Cyclothiazide: 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
Cyclothiazide
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.
You've been prescribed buprenorphine (an opioid pain or dependence medicine) along with cyclothiazide, which is a water pill (diuretic) that helps your body get rid of extra fluid. Opioids like buprenorphine can nudge your body to hold onto more water, which may make the water pill work a little less well. You might notice you're not passing as much urine, or your blood pressure or swelling isn't as controlled as expected.
The good news is that this concern is theoretical, meaning it's based on how these drugs could act rather than strong real-world proof. Keep taking both as prescribed, and your care team can easily manage this by watching how you respond and adjusting your water pill dose if needed.
Effect: Potentially reduced diuretic efficacy of cyclothiazide when combined with buprenorphine.
Mechanism: Opioids may induce antidiuretic hormone (ADH) release, promoting water retention and opposing the natriuretic/diuretic action. This is a PD interaction; neither agent's metabolism drives it.
Evidence: Theoretical; onset unspecified; magnitude not quantified. Severity rated major.
Management:
- Monitor urine output, fluid status, edema, blood pressure, and electrolytes.
- Titrate cyclothiazide dose upward as clinically indicated if diminished diuresis is observed.
- Individualize therapy; no fixed dose adjustment applies.
What happens
Reduced efficacy of diuretics
Interaction Deep Dive
When opioids such as buprenorphine are given together with diuretics, they may trigger the release of antidiuretic hormone, which can lessen how well the diuretics work. Watch patients for evidence of reduced diuresis and/or changes in blood pressure, and raise the diuretic dose when necessary1.
Why it happens (mechanism)
Induction of antidiuretic hormone release
How to manage this interaction
Keep taking both medications exactly as prescribed unless your prescriber tells you otherwise. This is a manageable situation.
- Your care team may watch how well the water pill is working, for example by checking your weight, swelling, urine output, and blood pressure.
- If your diuretic seems less effective, the dose may be adjusted and individualized by your team.
- Tell your pharmacist or doctor if you notice increased swelling, sudden weight gain, reduced urination, or blood pressure changes.
These simple checks let your team keep everything on track.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Buprenorphine and Cyclothiazide together?
Buprenorphine may slightly reduce how well cyclothiazide (a water pill) works by causing water retention. Keep taking both, and let your care team monitor your response and adjust the diuretic dose if needed. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Buprenorphine and Cyclothiazide 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 Cyclothiazide interaction managed?
Keep taking both medications exactly as prescribed unless your prescriber tells you otherwise. This is a manageable situation. Your care team may watch how well the water pill is working, for example by checking your weight, swelling, urine output, and blood pressure. If your diuretic seems less effective, the dose may be adjusted and individualized by your team. Tell your pharmacist or doctor if… 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 Buprenorphine or Cyclothiazide 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 (1)
- Product Information: BRIXADI(TM) subcutaneous extended-release injection, buprenorphine subcutaneous extended-release injection. Braeburn Inc (per FDA), Plymouth Meeting, PA, 2023. DailyMed
Keep reading about Buprenorphine
Keep reading about Cyclothiazide
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