Drug interactions
Darunavir + Mefloquine
Severity: Major
Darunavir and Mefloquine: major interaction.
Last updated Sources: US FDA label
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
Darunavir, usually given with a pharmacokinetic booster such as ritonavir or cobicistat, inhibits CYP3A4 and can raise mefloquine exposure. Higher mefloquine levels may increase neuropsychiatric and cardiac adverse effects, including QT prolongation. Mefloquine's long half-life means the risk persists after it is stopped.
What this interaction means in plain words
Darunavir and Mefloquine 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.
Darunavir belongs to Anti Virals; Mefloquine belongs to Anti Parasitic.
Why it happens
Inhibition of CYP3A4-mediated mefloquine metabolism by boosted darunavir increases mefloquine plasma concentrations.
What to do
Avoid the combination and choose another antimalarial for prophylaxis or treatment where possible. If unavoidable, monitor ECG and neuropsychiatric symptoms closely.
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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References
Other interactions of Mefloquine
- Arsenic trioxide + Mefloquine Contraindicated
- Dronedarone + Mefloquine Contraindicated
- Ibutilide + Mefloquine Contraindicated
- Levoketoconazole + Mefloquine Contraindicated
- Mefloquine + Nilotinib Contraindicated
- Mefloquine + Pimozide Contraindicated
Other interactions of Darunavir
- Alfuzosin + Darunavir Contraindicated
- Avanafil + Darunavir Contraindicated
- Darunavir + Dronedarone Contraindicated
- Darunavir + Eletriptan Contraindicated
- Darunavir + Ergotamine Contraindicated
- Darunavir + Flibanserin Contraindicated
Frequently asked questions
Can I take Darunavir with Mefloquine?
MediHelp rates the interaction as major. Darunavir and Mefloquine 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. Darunavir, usually given with a pharmacokinetic booster such as ritonavir or cobicistat, inhibits CYP3A4 and can raise mefloquine exposure. Higher mefloquine levels may increase neuropsychiatric and cardiac adverse effects, including QT prolongation. Mefloquine's long half-life means the risk persists after it is stopped.
How serious is the interaction between Darunavir and Mefloquine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination and choose another antimalarial for prophylaxis or treatment where possible. If unavoidable, monitor ECG and neuropsychiatric symptoms closely.
What other medicines interact with Mefloquine?
MediHelp also lists interactions of Mefloquine with, for example, Arsenic trioxide, Dronedarone, Ibutilide. The full list is on the Mefloquine page.
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