Drug interactions
Clozapine + Erythromycin lactobionate
Severity: Major
Clozapine and Erythromycin lactobionate: major interaction.
Last updated Sources: US FDA label
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
Intravenous erythromycin inhibits CYP3A4 and can raise clozapine levels, with reports of toxicity including seizures, sedation and cardiac effects. Both drugs can also prolong the QT interval, and IV dosing gives high peak levels.
What this interaction means in plain words
Clozapine and Erythromycin lactobionate 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.
Clozapine belongs to Central Nervous System; Erythromycin lactobionate belongs to Anti Bacterial.
Why it happens
CYP3A4 inhibition by erythromycin reduces clozapine clearance, combined with additive QT prolongation.
What to do
Prefer a non-macrolide antibiotic. If IV erythromycin is needed, monitor for clozapine toxicity, consider checking clozapine levels or reducing the dose, and monitor the 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 Clozapine
- Clozapine + Deferiprone Contraindicated
- Clozapine + Irinotecan Contraindicated
- Clozapine + Pimozide Contraindicated
- Clozapine + Thioridazine Contraindicated
- Acalabrutinib + Clozapine Major
- Adagrasib + Clozapine Major
Other interactions of Erythromycin lactobionate
- Cisapride + Erythromycin lactobionate Contraindicated
- Dihydroergotamine + Erythromycin lactobionate Contraindicated
- Dronedarone + Erythromycin lactobionate Contraindicated
- Eletriptan + Erythromycin lactobionate Contraindicated
- Ergotamine + Erythromycin lactobionate Contraindicated
- Erythromycin lactobionate + Flibanserin Contraindicated
Frequently asked questions
Can I take Clozapine with Erythromycin lactobionate?
MediHelp rates the interaction as major. Clozapine and Erythromycin lactobionate 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. Intravenous erythromycin inhibits CYP3A4 and can raise clozapine levels, with reports of toxicity including seizures, sedation and cardiac effects. Both drugs can also prolong the QT interval, and IV dosing gives high peak levels.
How serious is the interaction between Clozapine and Erythromycin lactobionate?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Prefer a non-macrolide antibiotic. If IV erythromycin is needed, monitor for clozapine toxicity, consider checking clozapine levels or reducing the dose, and monitor the ECG and electrolytes.
What other medicines interact with Clozapine?
MediHelp also lists interactions of Clozapine with, for example, Deferiprone, Irinotecan, Pimozide. The full list is on the Clozapine page.
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