Diazepam Rectal and Cobicistat: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Cobicistat
Diazepam Rectal
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
Increased diazepam exposure
Interaction Deep Dive
Coadministration of cobicistat (a strong CYP3A4 inhibitor) and diazepam (a CYP3A4 substrate) may result in increased diazepam plasma concentrations and an increased risk of toxicity. If concurrent use is required, initiate with a lower starting dose of diazepam1 and closely monitor patients for respiratory depression or prolonged sedation in a setting that provides for adequate medical management 2.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated diazepam metabolism
Common questions
Can I take Diazepam Rectal and Cobicistat together?
Increased diazepam exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Diazepam Rectal and Cobicistat 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 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 Diazepam Rectal or Cobicistat 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: SYMTUZA(TM) oral tablets, darunavir cobicistat emtricitabine tenofovir alafenamide oral tablets. Janssen Therapeutics (per manufacturer), Titusville, NJ, 2018. DailyMed
- Product Information: GENVOYA(R) oral tablets, elvitegravir, cobicistat, emtricitabine, tenofovir alafenamide oral tablets. Gilead Sciences, Inc. (per manufacturer), Foster City, CA, 2015. DailyMed
Keep reading about Cobicistat
Keep reading about Diazepam Rectal
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