Drug interactions
Azithromycin + Lefamulin
Severity: Major
Azithromycin and Lefamulin: 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
Lefamulin can prolong the QT interval, and azithromycin has a similar effect. Together they may increase the risk of torsades de pointes. Using two antibiotics from different classes for pneumonia is seldom necessary with lefamulin.
What this interaction means in plain words
Azithromycin and Lefamulin 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; Lefamulin belongs to Anti Bacterial.
Why it happens
Additive pharmacodynamic QT prolongation.
What to do
Avoid the combination and select another regimen. If it cannot be avoided, monitor ECG and correct potassium and magnesium.
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: medicinal products known to prolong the QT interval; "Azithromycin should be used with caution in patients receiving medicinal products known to prolong the QT interval") — 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 Lefamulin
- Lefamulin + Methadone Contraindicated
- Lefamulin + Pimavanserin Contraindicated
- Lefamulin + Pimozide Contraindicated
- Lefamulin + Quinidine Contraindicated
- Alfuzosin + Lefamulin Major
- Amiodarone + Lefamulin Major
Frequently asked questions
Can I take Azithromycin with Lefamulin?
MediHelp rates the interaction as major. Azithromycin and Lefamulin 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. Lefamulin can prolong the QT interval, and azithromycin has a similar effect. Together they may increase the risk of torsades de pointes. Using two antibiotics from different classes for pneumonia is seldom necessary with lefamulin.
How serious is the interaction between Azithromycin and Lefamulin?
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 and select another regimen. If it cannot be avoided, monitor ECG and correct potassium and magnesium.
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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