Drug interactions
Erythromycin + Mobocertinib
Severity: Major
Erythromycin and Mobocertinib: 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
Erythromycin increases mobocertinib exposure and both agents prolong the QT interval, creating a significant risk of torsade de pointes.
What this interaction means in plain words
Erythromycin and Mobocertinib 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
CYP3A4 inhibition raises mobocertinib levels, with additive QT prolongation.
What to do
Avoid and choose a non-inhibiting, non-QT-prolonging antibiotic. If unavoidable, reduce the mobocertinib dose per labeling and monitor ECG and 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
Other interactions of Erythromycin
- Conivaptan + Erythromycin Contraindicated
- Dihydroergotamine intranasal + Erythromycin Contraindicated
- Dihydroergotamine + Erythromycin Contraindicated
- Domperidone + Erythromycin Contraindicated
- Dronedarone + Erythromycin Contraindicated
- Droperidol + Erythromycin Contraindicated
Frequently asked questions
Can I take Erythromycin with Mobocertinib?
MediHelp rates the interaction as major. Erythromycin and Mobocertinib 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. Erythromycin increases mobocertinib exposure and both agents prolong the QT interval, creating a significant risk of torsade de pointes.
How serious is the interaction between Erythromycin and Mobocertinib?
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 and choose a non-inhibiting, non-QT-prolonging antibiotic. If unavoidable, reduce the mobocertinib dose per labeling and monitor ECG and electrolytes.
What other medicines interact with Erythromycin?
MediHelp also lists interactions of Erythromycin with, for example, Conivaptan, Dihydroergotamine intranasal, Dihydroergotamine. The full list is on the Erythromycin page.
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