Maraviroc and St John's Wort: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
St John's Wort
No brand names on recordMaraviroc
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 maraviroc exposure resulting in suboptimal levels of maraviroc that lead to loss of virologic response and possible resistance to maraviroc
Interaction Deep Dive
Concurrent use of maraviroc (a CYP3A substrate) with St Johns wort (CYP3A inducer) is not recommended as it may reduce maraviroc exposure and may result in suboptimal levels of maraviroc and lead to loss of virologic response and possible resistance to maraviroc. The concomitant use of maraviroc with St Johns wort (a strong CYP3A inducer) is contraindicated in adult and pediatric patients with CrCl less than 30 mL/min and in those with ESRD on regular hemodialysis. In adults with CrCl 30 mL/min or greater treated with maraviroc and a concurrent strong CYP3A inducer (and no strong CYP3A inhibitors), increase the maraviroc dose to 600 mg orally twice daily. In pediatric patients with CrCl 30 mL/min or greater, concomitant use of maraviroc and strong CYP3A inducers is not recommended1.
Why it happens (mechanism)
Induction of CYP3A-mediated metabolism of maraviroc
Common questions
Can I take Maraviroc and St John's Wort together?
Reduced maraviroc exposure resulting in suboptimal levels of maraviroc that lead to loss of virologic response and possible resistance to maraviroc Always confirm with your pharmacist or prescriber before making any change.
How serious is the Maraviroc and St John's Wort 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 Maraviroc or St John's Wort 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: SELZENTRY(R) oral tablets, oral solution, maraviroc oral tablets, oral solution. Viiv Healthcare (per manufacturer), Research Triangle Park, NC, 2016. DailyMed
Keep reading about St John's Wort
Keep reading about Maraviroc
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