Drug interactions
Fostemsavir + Quinine
Severity: Moderate
Fostemsavir and Quinine: 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
Fostemsavir has caused QTc prolongation at supratherapeutic doses, and quinine also prolongs QTc. Together they may raise the risk of torsades de pointes, especially in patients with other risk factors.
What this interaction means in plain words
Fostemsavir and Quinine 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; Quinine belongs to Anti Parasitic.
Why it happens
Additive prolongation of cardiac repolarization.
What to do
Obtain an ECG and correct potassium and magnesium before and during combined use. Avoid in patients with congenital long QT syndrome or other QT-prolonging drugs.
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 Quinine
- Arsenic trioxide + Quinine Contraindicated
- Dofetilide + Quinine Contraindicated
- Dronedarone + Quinine Contraindicated
- Ibutilide + Quinine Contraindicated
- Mefloquine + Quinine Contraindicated
- Nilotinib + Quinine 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 Quinine?
MediHelp rates the interaction as moderate. Fostemsavir and Quinine 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 has caused QTc prolongation at supratherapeutic doses, and quinine also prolongs QTc. Together they may raise the risk of torsades de pointes, especially in patients with other risk factors.
How serious is the interaction between Fostemsavir and Quinine?
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 an ECG and correct potassium and magnesium before and during combined use. Avoid in patients with congenital long QT syndrome or other QT-prolonging drugs.
What other medicines interact with Quinine?
MediHelp also lists interactions of Quinine with, for example, Arsenic trioxide, Dofetilide, Dronedarone. The full list is on the Quinine page.
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