Drug interactions
Erythromycin lactobionate + Fluphenazine
Severity: Major
Erythromycin lactobionate and Fluphenazine: major 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
Intravenous erythromycin prolongs the QT interval, particularly with rapid infusion, and may increase the risk of torsades de pointes when added to fluphenazine. The risk is greater with electrolyte disturbances or heart disease.
What this interaction means in plain words
Erythromycin lactobionate and Fluphenazine 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; Fluphenazine belongs to Central Nervous System.
Why it happens
Additive QT prolongation; erythromycin may also modestly raise phenothiazine levels via CYP3A4 inhibition.
What to do
Prefer a non-QT-prolonging antibiotic; if erythromycin is needed, infuse slowly, correct potassium and magnesium, and monitor ECG.
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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Other interactions of Fluphenazine
- Arsenic trioxide + Fluphenazine Contraindicated
- Dofetilide + Fluphenazine Contraindicated
- Fluphenazine + Ibutilide Contraindicated
- Fluphenazine + Pimozide Contraindicated
- Adagrasib + Fluphenazine Major
- Alfentanil + Fluphenazine 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 Erythromycin lactobionate with Fluphenazine?
MediHelp rates the interaction as major. Erythromycin lactobionate and Fluphenazine 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 prolongs the QT interval, particularly with rapid infusion, and may increase the risk of torsades de pointes when added to fluphenazine. The risk is greater with electrolyte disturbances or heart disease.
How serious is the interaction between Erythromycin lactobionate and Fluphenazine?
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-QT-prolonging antibiotic; if erythromycin is needed, infuse slowly, correct potassium and magnesium, and monitor ECG.
What other medicines interact with Fluphenazine?
MediHelp also lists interactions of Fluphenazine with, for example, Arsenic trioxide, Dofetilide, Ibutilide. The full list is on the Fluphenazine page.
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