Drug interactions
Fluoxetine + Moxifloxacin
Severity: Moderate
Fluoxetine and Moxifloxacin: 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
Both drugs can prolong the QT interval, so combined use may increase the risk of torsades de pointes. Risk is higher with electrolyte disturbance, bradycardia or other QT-prolonging drugs.
What this interaction means in plain words
Fluoxetine and Moxifloxacin 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; Moxifloxacin belongs to Anti Bacterial.
Why it happens
Additive blockade of cardiac hERG potassium channels, prolonging ventricular repolarization.
What to do
Check a baseline ECG and correct potassium and magnesium. Monitor the QTc in patients with additional risk factors, or choose another antibiotic.
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 Moxifloxacin
- Amiodarone + Moxifloxacin Contraindicated
- Arsenic trioxide + Moxifloxacin Contraindicated
- Disopyramide + Moxifloxacin Contraindicated
- Dofetilide + Moxifloxacin Contraindicated
- Dronedarone + Moxifloxacin Contraindicated
- Droperidol + Moxifloxacin 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 Moxifloxacin?
MediHelp rates the interaction as moderate. Fluoxetine and Moxifloxacin 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. Both drugs can prolong the QT interval, so combined use may increase the risk of torsades de pointes. Risk is higher with electrolyte disturbance, bradycardia or other QT-prolonging drugs.
How serious is the interaction between Fluoxetine and Moxifloxacin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check a baseline ECG and correct potassium and magnesium. Monitor the QTc in patients with additional risk factors, or choose another antibiotic.
What other medicines interact with Moxifloxacin?
MediHelp also lists interactions of Moxifloxacin with, for example, Amiodarone, Arsenic trioxide, Disopyramide. The full list is on the Moxifloxacin page.
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