Drug interactions
Azithromycin + Ibutilide
Severity: Major
Azithromycin and Ibutilide: major interaction.
Last updated Sources: UK SmPC
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
Ibutilide markedly prolongs the QT interval and carries a substantial risk of torsades de pointes; adding azithromycin increases this risk further.
What this interaction means in plain words
Azithromycin and Ibutilide 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.
Azithromycin belongs to Anti Bacterial; Ibutilide belongs to Cardiovascular.
Why it happens
Additive prolongation of cardiac repolarisation and QT interval.
What to do
Avoid using these together; if cardioversion with ibutilide is needed, use an alternative antibiotic and ensure continuous ECG monitoring and normal electrolytes.
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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References
- Azithromycin 200mg/5ml Powder for Oral Suspension - SmPC sections 4.3/4.5 (class statement: antiarrhythmics of Classes IA (e.g. quinidine and procainamide) and III; "antiarrhythmics of Classes IA (e.g. quinidine and procainamide) and III (e.g. dofetilide, amiodarone and sotalol)") — electronic medicines compendium (UK SmPC)
Other interactions of Azithromycin
- Azithromycin + Cisapride Contraindicated
- Azithromycin + Domperidone Contraindicated
- Azithromycin + Dronedarone Contraindicated
- Azithromycin + Pimozide Contraindicated
- Azithromycin + Piperaquine Contraindicated
- Azithromycin + Thioridazine Contraindicated
Other interactions of Ibutilide
- Amiodarone + Ibutilide Contraindicated
- Amisulpride + Ibutilide Contraindicated
- Chlorpromazine + Ibutilide Contraindicated
- Clarithromycin + Ibutilide Contraindicated
- Desipramine + Ibutilide Contraindicated
- Dolasetron + Ibutilide Contraindicated
Frequently asked questions
Can I take Azithromycin with Ibutilide?
MediHelp rates the interaction as major. Azithromycin and Ibutilide 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. Ibutilide markedly prolongs the QT interval and carries a substantial risk of torsades de pointes; adding azithromycin increases this risk further.
How serious is the interaction between Azithromycin and Ibutilide?
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 using these together; if cardioversion with ibutilide is needed, use an alternative antibiotic and ensure continuous ECG monitoring and normal electrolytes.
What other medicines interact with Azithromycin?
MediHelp also lists interactions of Azithromycin with, for example, Cisapride, Domperidone, Dronedarone. The full list is on the Azithromycin page.
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