Drug interactions
Gemifloxacin + Phenytoin
Severity: Moderate
Gemifloxacin and Phenytoin: 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
Fluoroquinolones have been reported to change phenytoin concentrations unpredictably, in some cases lowering them and in others raising them. Loss of seizure control or phenytoin toxicity is possible, though reports are sparse.
What this interaction means in plain words
Gemifloxacin and Phenytoin 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.
Gemifloxacin belongs to Anti Bacterial; Phenytoin belongs to Central Nervous System.
Why it happens
The mechanism is not established; altered absorption or metabolism of phenytoin has been proposed.
What to do
Monitor phenytoin levels and clinical response for seizures or toxicity during and after the antibiotic course. Adjust the phenytoin dose according to levels.
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 Gemifloxacin
- Arsenic trioxide + Gemifloxacin Contraindicated
- Dofetilide + Gemifloxacin Contraindicated
- Gemifloxacin + Ibutilide Contraindicated
- Gemifloxacin + Pimozide Contraindicated
- Gemifloxacin + Thioridazine Contraindicated
- Gemifloxacin + Vandetanib Contraindicated
Other interactions of Phenytoin
- Artemether / lumefantrine + Phenytoin Contraindicated
- Bictegravir + Phenytoin Contraindicated
- Cabotegravir + Phenytoin Contraindicated
- Doravirine + Phenytoin Contraindicated
- Elbasvir / grazoprevir + Phenytoin Contraindicated
- Elvitegravir / cobicistat / emtricitabine / tenofovir df + Phenytoin Contraindicated
Frequently asked questions
Can I take Gemifloxacin with Phenytoin?
MediHelp rates the interaction as moderate. Gemifloxacin and Phenytoin 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. Fluoroquinolones have been reported to change phenytoin concentrations unpredictably, in some cases lowering them and in others raising them. Loss of seizure control or phenytoin toxicity is possible, though reports are sparse.
How serious is the interaction between Gemifloxacin and Phenytoin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor phenytoin levels and clinical response for seizures or toxicity during and after the antibiotic course. Adjust the phenytoin dose according to levels.
What other medicines interact with Gemifloxacin?
MediHelp also lists interactions of Gemifloxacin with, for example, Arsenic trioxide, Dofetilide, Ibutilide. The full list is on the Gemifloxacin page.
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