Drug interactions
Fostemsavir + Gemifloxacin
Severity: Moderate
Fostemsavir and Gemifloxacin: 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
Gemifloxacin can prolong the QT interval, and fostemsavir has been associated with QT prolongation at supratherapeutic doses. Combined use may modestly raise the risk of torsades de pointes, particularly with other risk factors.
What this interaction means in plain words
Fostemsavir and Gemifloxacin 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.
Fostemsavir belongs to Anti Virals; Gemifloxacin belongs to Anti Bacterial.
Why it happens
Additive prolongation of cardiac repolarization (QT interval) through pharmacodynamic effects.
What to do
Correct hypokalemia and hypomagnesemia and consider baseline and follow-up ECG in patients with cardiac risk factors. Use an alternative antibiotic if the patient has other QT risk factors.
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 Fostemsavir
- Apalutamide + Fostemsavir Contraindicated
- Carbamazepine + Fostemsavir Contraindicated
- Enzalutamide + Fostemsavir Contraindicated
- Fostemsavir + Mitotane Contraindicated
- Fostemsavir + Phenytoin Contraindicated
- Fostemsavir + Rifampicin Contraindicated
Frequently asked questions
Can I take Fostemsavir with Gemifloxacin?
MediHelp rates the interaction as moderate. Fostemsavir and Gemifloxacin 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 can prolong the QT interval, and fostemsavir has been associated with QT prolongation at supratherapeutic doses. Combined use may modestly raise the risk of torsades de pointes, particularly with other risk factors.
How serious is the interaction between Fostemsavir and Gemifloxacin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Correct hypokalemia and hypomagnesemia and consider baseline and follow-up ECG in patients with cardiac risk factors. Use an alternative antibiotic if the patient has other QT risk factors.
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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