Drug interactions
Quinine + Voriconazole
Severity: Major
Quinine and Voriconazole: major 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 prolong the QT interval, and voriconazole can inhibit CYP3A4-mediated quinine metabolism, increasing quinine levels. This raises the risk of serious ventricular arrhythmias, as well as cinchonism.
What this interaction means in plain words
Quinine and Voriconazole can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Quinine belongs to Anti Parasitic; Voriconazole belongs to Anti Fungals.
Why it happens
Additive QT prolongation plus CYP3A4 inhibition increasing quinine exposure.
What to do
Avoid the combination where possible; if needed, obtain a baseline ECG, correct electrolytes and monitor ECG throughout treatment.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Voriconazole
- Avanafil + Voriconazole Contraindicated
- Butabarbital + Voriconazole Contraindicated
- Carbamazepine + Voriconazole Contraindicated
- Conivaptan + Voriconazole Contraindicated
- Dihydroergotamine intranasal + Voriconazole Contraindicated
- Dihydroergotamine + Voriconazole Contraindicated
Other interactions of Quinine
- Arsenic trioxide + Quinine Contraindicated
- Dofetilide + Quinine Contraindicated
- Dronedarone + Quinine Contraindicated
- Ibutilide + Quinine Contraindicated
- Mefloquine + Quinine Contraindicated
- Nilotinib + Quinine Contraindicated
Frequently asked questions
Can I take Quinine with Voriconazole?
MediHelp rates the interaction as major. Quinine and Voriconazole can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Both drugs prolong the QT interval, and voriconazole can inhibit CYP3A4-mediated quinine metabolism, increasing quinine levels. This raises the risk of serious ventricular arrhythmias, as well as cinchonism.
How serious is the interaction between Quinine and Voriconazole?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible; if needed, obtain a baseline ECG, correct electrolytes and monitor ECG throughout treatment.
What other medicines interact with Voriconazole?
MediHelp also lists interactions of Voriconazole with, for example, Avanafil, Butabarbital, Carbamazepine. The full list is on the Voriconazole page.
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