Drug interactions
Fluoxetine + Mefloquine
Severity: Moderate
Fluoxetine and Mefloquine: moderate 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
Fluoxetine has a modest QT-prolonging effect and mefloquine may add to this. Fluoxetine also inhibits CYP2D6 and CYP3A4 to some degree, though mefloquine kinetics are not clearly affected.
What this interaction means in plain words
Fluoxetine and Mefloquine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Fluoxetine belongs to Central Nervous System; Mefloquine belongs to Anti Parasitic.
Why it happens
Possible additive QT prolongation.
What to do
Obtain a baseline ECG and correct electrolytes if co-used, especially with other QT risk factors. Consider an alternative antimalarial in high-risk patients.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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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 Fluoxetine
- Fluoxetine + Isocarboxazid Contraindicated
- Fluoxetine + Mavacamten Contraindicated
- Fluoxetine + Methylene blue Contraindicated
- Fluoxetine + Phenelzine Contraindicated
- Fluoxetine + Pimozide Contraindicated
- Fluoxetine + Rasagiline Contraindicated
Frequently asked questions
Can I take Fluoxetine with Mefloquine?
MediHelp rates the interaction as moderate. Fluoxetine and Mefloquine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Fluoxetine has a modest QT-prolonging effect and mefloquine may add to this. Fluoxetine also inhibits CYP2D6 and CYP3A4 to some degree, though mefloquine kinetics are not clearly affected.
How serious is the interaction between Fluoxetine and Mefloquine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain a baseline ECG and correct electrolytes if co-used, especially with other QT risk factors. Consider an alternative antimalarial in high-risk patients.
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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