Drug interactions
Lefamulin + Mefloquine
Severity: Major
Lefamulin and Mefloquine: 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
Lefamulin inhibits CYP3A and prolongs the QT interval, and mefloquine can also affect cardiac conduction. Combined use may raise mefloquine exposure and increase the risk of serious arrhythmia.
What this interaction means in plain words
Lefamulin 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.
Lefamulin belongs to Anti Bacterial; Mefloquine belongs to Anti Parasitic.
Why it happens
Additive QT prolongation, with CYP3A4 inhibition by lefamulin reducing mefloquine clearance.
What to do
Avoid the combination and consider an alternative antibiotic or antimalarial. If it must be used, check ECG and electrolytes and monitor for neuropsychiatric effects.
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 Mefloquine
- Arsenic trioxide + Mefloquine Contraindicated
- Dronedarone + Mefloquine Contraindicated
- Ibutilide + Mefloquine Contraindicated
- Levoketoconazole + Mefloquine Contraindicated
- Mefloquine + Nilotinib Contraindicated
- Mefloquine + Pimozide Contraindicated
Other interactions of Lefamulin
- Lefamulin + Methadone Contraindicated
- Lefamulin + Pimavanserin Contraindicated
- Lefamulin + Pimozide Contraindicated
- Lefamulin + Quinidine Contraindicated
- Alfuzosin + Lefamulin Major
- Amiodarone + Lefamulin Major
Frequently asked questions
Can I take Lefamulin with Mefloquine?
MediHelp rates the interaction as major. Lefamulin 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. Lefamulin inhibits CYP3A and prolongs the QT interval, and mefloquine can also affect cardiac conduction. Combined use may raise mefloquine exposure and increase the risk of serious arrhythmia.
How serious is the interaction between Lefamulin 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 consider an alternative antibiotic or antimalarial. If it must be used, check ECG and electrolytes and monitor for neuropsychiatric effects.
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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