Midazolam Injection and Rifapentine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Rifapentine
Midazolam Injection
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.
What happens
Reduced diazepam plasma concentrations and effectiveness
Interaction Deep Dive
Concurrent use of rifapentine and a benzodiazepine has resulted in reduced benzodiazepine serum concentrations and effectiveness. Rifapentine probably induces hepatic microsomal enzymes which metabolizes the benzodiazepine1.
Why it happens (mechanism)
Induction of benzodiazepine metabolism
Common questions
Can I take Midazolam Injection and Rifapentine together?
Reduced diazepam plasma concentrations and effectiveness Always confirm with your pharmacist or prescriber before making any change.
How serious is the Midazolam Injection and Rifapentine interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
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 Midazolam Injection or Rifapentine 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: Priftin(R), rifapentine. Aventis Pharmaceuticals, Inc. Kansas City, MO, 2000. DailyMed
Keep reading about Rifapentine
Keep reading about Midazolam Injection
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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