Maraviroc and Ketoconazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ketoconazole
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 and an increased maraviroc-related adverse reactions
Interaction Deep Dive
Use caution with the concurrent use of maraviroc and ketoconazole. Upon coadministration, monitor patients closely for signs or symptoms of increased or prolonged effects or side effects of maraviroc, and reduce maraviroc dose as deemed necessary2. The concomitant use of maraviroc (a CYP3A substrate) with a potent CYP3A inhibitor may increase maraviroc exposure. Also, coadministration 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 taking a concurrent strong CYP3A inhibitor (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 CYP3A4-mediated metabolism of maraviroc
Literature reports
8 reports — tap to read
a) Concomitant administration of ketoconazole (a strong CYP3A inhibitor) and maraviroc resulted in increased maraviroc AUC and plasma concentrations. When ketoconazole 400 mg once daily was administered concurrently with maraviroc 100 mg twice daily in 12 patients, the ratio of maraviroc pharmacokinetic parameters with ketoconazole to without ketoconazole was: Cmin 3.75 (90% CI, 3.01 to 4.69), AUC 5 (90% CI, 3.98 to 6.29), and Cmax 3.38 (90% CI, 2.38 to 4.78) 1.
b) Concomitant administration of lopinavir/ritonavir (a strong CYP3A inhibitor) and maraviroc resulted in increased maraviroc AUC and plasma concentrations. When lopinavir 400 mg/ritonavir 100 mg twice daily was administered concurrently with maraviroc 300 mg twice daily in 11 patients, the ratio of maraviroc pharmacokinetic parameters with lopinavir/ritonavir to without lopinavir/ritonavir was: Cmin 9.24 (90% CI, 7.98 to 10.7), AUC 3.95 (90% CI, 3.43 to 4.56), and Cmax 1.97 (90% CI, 1.66 to 2.34) 1.
c) Concomitant administration of maraviroc and lopinavir/ritonavir (a strong CYP3A inhibitor) plus efavirenz resulted in increased maraviroc AUC and plasma concentrations. When maraviroc 300 mg twice daily was administered concurrently with lopinavir 400 mg/ritonavir 100 mg twice daily plus efavirenz 600 mg once daily in 11 patients, the ratio of maraviroc pharmacokinetic parameters with lopinavir/ritonavir plus efavirenz to without lopinavir/ritonavir plus efavirenz was: Cmin 6.29 (90% CI, 4.72-8.39), AUC 2.53 (90% CI, 2.24-2.87), and Cmax 1.25 (90% CI, 1.01 to 1.55) 1.
d) Concomitant administration of maraviroc and ritonavir (a strong CYP3A inhibitor) resulted in increased maraviroc AUC and plasma concentrations. When ritonavir 100 mg twice daily was administered concurrently with maraviroc 100 mg twice daily in 8 patients, the ratio of maraviroc pharmacokinetic parameters with ritonavir to without ritonavir was: Cmin 4.55 (90% CI, 3.37 to 6.13), AUC 2.61 (90% CI, 1.92 to 3.56), and Cmax 1.28 (90% CI, 0.79 to 2.09) 1.
e) Concomitant administration of maraviroc and saquinavir/ritonavir (a strong CYP3A inhibitor) resulted in increased maraviroc AUC and plasma concentrations. When saquinavir 1000 mg/ritonavir 100 mg twice daily was administered concurrently with maraviroc 100 mg twice daily in 11 patients, the ratio of maraviroc pharmacokinetic parameters with saquinavir/ritonavir to without saquinavir/ritonavir was: Cmin 11.3 (90% CI, 8.96 to 14.1), AUC 9.77 (90% CI, 7.87 to 12.14), and Cmax 4.78 (90% CI, 3.41 to 6.71) 1.
f) Concomitant administration of maraviroc and saquinavir/ritonavir (a strong CYP3A inhibitor) plus efavirenz resulted in increased maraviroc AUC and plasma concentrations. When maraviroc 100 mg twice daily was administered concurrently with saquinavir 1000 mg/ritonavir 100 mg twice daily plus efavirenz 600 mg once daily in 11 patients, the ratio of maraviroc pharmacokinetic parameters with saquinavir/ritonavir plus efavirenz to without saquinavir/ritonavir plus efavirenz was: Cmin 8.42 (90% CI, 6.46 to 10.97), AUC 5 (90% CI, 4.26 to 5.87), and Cmax 2.26 (90% CI, 1.64 to 3.11) 1.
g) When maraviroc 150 mg twice daily was administered concurrently with boceprevir 800 mg three times/day (N=14), maraviroc AUC was increased 3-fold and Cmax was increased 3.33-fold 1.
h) When maraviroc 150 mg twice daily was administered concurrently with elvitegravir 150 mg/ritonavir 100 mg once daily (N=11), maraviroc AUC was increased 2.86-fold and Cmax was increased 2.15-fold 1.
Common questions
Can I take Maraviroc and Ketoconazole together?
Increased maraviroc exposure and an increased maraviroc-related adverse reactions Always confirm with your pharmacist or prescriber before making any change.
How serious is the Maraviroc and Ketoconazole 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 "established". Well documented — supported by controlled studies or strong clinical data.
Questions for your pharmacist
- Does my dose of Maraviroc or Ketoconazole 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 manufacturer), Research Triangle Park, NC, 2016. DailyMed
- Product Information: Ketoconazole oral tablet, ketoconazole oral tablet. Taro Pharmaceuticals U.S.A. Inc. (per DailyMed), Hawthorne, NY, 2024. DailyMed
Keep reading about Ketoconazole
Keep reading about Maraviroc
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Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
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