Drug interactions
Erythromycin lactobionate + Mifepristone
Severity: Major
Erythromycin lactobionate and Mifepristone: major interaction.
Last updated Sources: Base de donnees publique des medicaments (France)
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
Mifepristone inhibits CYP3A4, and intravenous erythromycin is a CYP3A4 substrate that prolongs the QT interval. Increased erythromycin exposure may raise the risk of torsades de pointes. Erythromycin may also increase mifepristone concentrations.
What this interaction means in plain words
Erythromycin lactobionate and Mifepristone 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 lactobionate belongs to Anti Bacterial; Mifepristone belongs to Endocrine.
Why it happens
Mifepristone inhibits CYP3A4-mediated metabolism of erythromycin, with additive QT-prolonging effects.
What to do
Choose a non-macrolide alternative where possible. If unavoidable, monitor the ECG QTc and keep potassium and magnesium within normal range.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Erythromycin lactobionate and Mifepristone, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
References
Other interactions of Mifepristone
- Apixaban + Mifepristone Contraindicated
- Argatroban + Mifepristone Contraindicated
- Cisapride + Mifepristone Contraindicated
- Cortisone + Mifepristone Contraindicated
- Cyclosporin + Mifepristone Contraindicated
- Dabigatran etexilate + Mifepristone Contraindicated
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 Erythromycin lactobionate with Mifepristone?
MediHelp rates the interaction as major. Erythromycin lactobionate and Mifepristone 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. Mifepristone inhibits CYP3A4, and intravenous erythromycin is a CYP3A4 substrate that prolongs the QT interval. Increased erythromycin exposure may raise the risk of torsades de pointes. Erythromycin may also increase mifepristone concentrations.
How serious is the interaction between Erythromycin lactobionate and Mifepristone?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Choose a non-macrolide alternative where possible. If unavoidable, monitor the ECG QTc and keep potassium and magnesium within normal range.
What other medicines interact with Mifepristone?
MediHelp also lists interactions of Mifepristone with, for example, Apixaban, Argatroban, Cisapride. The full list is on the Mifepristone page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
