Drug interactions
Lumefantrine + Mefloquine
Severity: Major
Lumefantrine 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
Both drugs prolong the QT interval, and lumefantrine is labeled with warnings about use with other QT-prolonging antimalarials. Giving lumefantrine after mefloquine may also reduce lumefantrine exposure. The combination raises the risk of arrhythmia and may compromise efficacy.
What this interaction means in plain words
Lumefantrine 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.
Why it happens
Additive QT prolongation, with possible pharmacokinetic effects on lumefantrine exposure.
What to do
Avoid sequential or concurrent use where possible, particularly if mefloquine was taken recently. If treatment is essential, monitor the ECG and electrolytes.
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
Frequently asked questions
Can I take Lumefantrine with Mefloquine?
MediHelp rates the interaction as major. Lumefantrine 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. Both drugs prolong the QT interval, and lumefantrine is labeled with warnings about use with other QT-prolonging antimalarials. Giving lumefantrine after mefloquine may also reduce lumefantrine exposure. The combination raises the risk of arrhythmia and may compromise efficacy.
How serious is the interaction between Lumefantrine 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 sequential or concurrent use where possible, particularly if mefloquine was taken recently. If treatment is essential, monitor the ECG and electrolytes.
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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