Drug interactions
Azithromycin + Erythromycin base
Severity: Moderate
Azithromycin and Erythromycin base: 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
Both macrolides can prolong the QT interval, so using them together adds arrhythmia risk without a therapeutic benefit in most cases. Azithromycin may also modestly increase erythromycin exposure via P-glycoprotein.
What this interaction means in plain words
Azithromycin and Erythromycin base 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.
Why it happens
Additive QT prolongation, with possible P-glycoprotein inhibition.
What to do
Avoid concurrent use of two macrolides unless specifically indicated. If both are needed, monitor ECG and electrolytes.
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 Azithromycin
- Azithromycin + Cisapride Contraindicated
- Azithromycin + Domperidone Contraindicated
- Azithromycin + Dronedarone Contraindicated
- Azithromycin + Pimozide Contraindicated
- Azithromycin + Piperaquine Contraindicated
- Azithromycin + Thioridazine Contraindicated
Frequently asked questions
Can I take Azithromycin with Erythromycin base?
MediHelp rates the interaction as moderate. Azithromycin and Erythromycin base 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. Both macrolides can prolong the QT interval, so using them together adds arrhythmia risk without a therapeutic benefit in most cases. Azithromycin may also modestly increase erythromycin exposure via P-glycoprotein.
How serious is the interaction between Azithromycin and Erythromycin base?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid concurrent use of two macrolides unless specifically indicated. If both are needed, monitor ECG and 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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