Drug interactions
Mefloquine + Procainamide
Severity: Major
Mefloquine and Procainamide: 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 can prolong the QT interval and procainamide carries a known risk of torsades de pointes. Combined use may add to the risk of serious ventricular arrhythmias.
What this interaction means in plain words
Mefloquine and Procainamide 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.
Why it happens
Additive prolongation of cardiac repolarization (QTc) through pharmacodynamic effects.
What to do
Avoid the combination if possible and use a non-QT-prolonging antimalarial. If unavoidable, obtain a baseline ECG, correct potassium and magnesium, and monitor the QTc.
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 Mefloquine
- Arsenic trioxide + Mefloquine Contraindicated
- Dronedarone + Mefloquine Contraindicated
- Ibutilide + Mefloquine Contraindicated
- Levoketoconazole + Mefloquine Contraindicated
- Mefloquine + Nilotinib Contraindicated
- Mefloquine + Pimozide Contraindicated
Frequently asked questions
Can I take Mefloquine with Procainamide?
MediHelp rates the interaction as major. Mefloquine and Procainamide 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 can prolong the QT interval and procainamide carries a known risk of torsades de pointes. Combined use may add to the risk of serious ventricular arrhythmias.
How serious is the interaction between Mefloquine and Procainamide?
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 if possible and use a non-QT-prolonging antimalarial. If unavoidable, obtain a baseline ECG, correct potassium and magnesium, and monitor the QTc.
What other medicines interact with Mefloquine?
MediHelp also lists interactions of Mefloquine with, for example, Arsenic trioxide, Dronedarone, Ibutilide. The full list is on the Mefloquine page.
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