Drug interactions
Maraviroc + Ritonavir
Severity: Major
Maraviroc and Ritonavir: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Ritonavir inhibits CYP3A and markedly raises maraviroc concentrations. This can increase adverse effects such as postural hypotension, hepatotoxicity and infections.
What this interaction means in plain words
Maraviroc and Ritonavir can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Maraviroc belongs to Anti Virals; Ritonavir belongs to Anti Virals.
Why it happens
Inhibition of CYP3A4 (and P-gp) by ritonavir reduces maraviroc first-pass and systemic metabolism.
What to do
Reduce maraviroc to 150 mg twice daily when given with ritonavir-boosted protease inhibitors, except tipranavir/ritonavir. Monitor for postural hypotension and liver toxicity.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Maraviroc
- Amobarbital + Maraviroc Major
- Apalutamide + Maraviroc Major
- Carbamazepine + Maraviroc Major
- Clarithromycin + Maraviroc Major
- Efavirenz + Maraviroc Major
- Enzalutamide + Maraviroc Major
Other interactions of Ritonavir
- Alfuzosin + Ritonavir Contraindicated
- Amiodarone + Ritonavir Contraindicated
- Avanafil + Ritonavir Contraindicated
- Colchicine + Ritonavir Contraindicated
- Dronedarone + Ritonavir Contraindicated
- Eletriptan + Ritonavir Contraindicated
Frequently asked questions
Can I take Maraviroc with Ritonavir?
MediHelp rates the interaction as major. Maraviroc and Ritonavir can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Ritonavir inhibits CYP3A and markedly raises maraviroc concentrations. This can increase adverse effects such as postural hypotension, hepatotoxicity and infections.
How serious is the interaction between Maraviroc and Ritonavir?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reduce maraviroc to 150 mg twice daily when given with ritonavir-boosted protease inhibitors, except tipranavir/ritonavir. Monitor for postural hypotension and liver toxicity.
What other medicines interact with Maraviroc?
MediHelp also lists interactions of Maraviroc with, for example, Amobarbital, Apalutamide, Carbamazepine. The full list is on the Maraviroc page.
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