Maraviroc and Conivaptan: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Conivaptan
Maraviroc
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 maraviroc exposure
Interaction Deep Dive
Concurrent use of conivaptan (strong CYP3A inhibitor) with maraviroc (CYP3A substrate) should be avoided2 and is contraindicated in patients with severe renal impairment (CrCl less than 30 mL/min) and ESRD on regular hemodialysis 1. Maraviroc may be initiated no sooner than 1 week after completion of conivaptan therapy 2. In adults with CrCl 30 mL/min or greater who require concomitant use of maraviroc and conivaptan (with or without a strong CYP3A inducer), reduce the maraviroc dose to 150 mg orally twice daily. In pediatric patients with CrCl 30 mL/min or greater, reduce the dose as follows: 50 mg twice daily for those 10 to less than 20 kg, 75 mg (if taking the tablet) or 80 mg (if taking oral solution) twice daily for those 20 to less than 30 kg), 100 mg twice daily for those 30 to less than 40 kg, and 150 mg twice daily for those 40 kg or greater 1.
Why it happens (mechanism)
Inhibition of CYP3A-mediated maraviroc metabolism
Common questions
Can I take Maraviroc and Conivaptan together?
Increased maraviroc exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Maraviroc and Conivaptan interaction?
It is rated contraindicated. These should generally not be used together.
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 Maraviroc or Conivaptan 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: SELZENTRY(R) oral tablets, oral solution, maraviroc oral tablets, oral solution. Viiv Healthcare (per FDA), Research Triangle Park, NC, 2018. DailyMed
- Product Information: VAPRISOL(R) intravenous injection, conivaptan HCl intravenous injection. Cumberland Pharmaceuticals Inc (per FDA), Nashville, TN, 2016.
Keep reading about Conivaptan
Keep reading about Maraviroc
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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