Drug interactions
Fluconazole + Mefloquine
Severity: Major
Fluconazole 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
Mefloquine is metabolized by CYP3A4 and can prolong QT and cause neuropsychiatric effects. Fluconazole may raise mefloquine levels and add its own QT liability, increasing the risk of arrhythmia.
What this interaction means in plain words
Fluconazole 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.
Fluconazole belongs to Anti Fungals; Mefloquine belongs to Anti Parasitic.
Why it happens
CYP3A4 inhibition by fluconazole increases mefloquine exposure, with additive QT prolongation.
What to do
Avoid the combination if possible, and choose an alternative antimalarial or antifungal. If unavoidable, check ECG and electrolytes and monitor for neuropsychiatric symptoms.
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 Fluconazole
- Dihydroergotamine intranasal + Fluconazole Contraindicated
- Dihydroergotamine + Fluconazole Contraindicated
- Dofetilide + Fluconazole Contraindicated
- Domperidone + Fluconazole Contraindicated
- Dronedarone + Fluconazole Contraindicated
- Erythromycin + Fluconazole Contraindicated
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 Fluconazole with Mefloquine?
MediHelp rates the interaction as major. Fluconazole 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. Mefloquine is metabolized by CYP3A4 and can prolong QT and cause neuropsychiatric effects. Fluconazole may raise mefloquine levels and add its own QT liability, increasing the risk of arrhythmia.
How serious is the interaction between Fluconazole 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 if possible, and choose an alternative antimalarial or antifungal. If unavoidable, check ECG and electrolytes and monitor for neuropsychiatric symptoms.
What other medicines interact with Fluconazole?
MediHelp also lists interactions of Fluconazole with, for example, Dihydroergotamine intranasal, Dihydroergotamine, Dofetilide. The full list is on the Fluconazole page.
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