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Drug interactions

Erythromycin lactobionate + Moxifloxacin

Severity: Major

Erythromycin lactobionate and Moxifloxacin: 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 gives high peak levels and, with moxifloxacin, adds to QT prolongation. This raises the risk of torsades de pointes, especially in hospitalized patients with electrolyte disturbances.

What this interaction means in plain words

Erythromycin lactobionate and Moxifloxacin 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; Moxifloxacin belongs to Anti Bacterial.

Evidence level: Moderate

Why it happens

Additive pharmacodynamic QT prolongation via hERG potassium channel blockade.

What to do

Avoid the combination and use an alternative antibiotic. If unavoidable, monitor ECG continuously or frequently and correct potassium and magnesium.

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?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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References

Frequently asked questions

Can I take Erythromycin lactobionate with Moxifloxacin?

MediHelp rates the interaction as major. Erythromycin lactobionate and Moxifloxacin 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 gives high peak levels and, with moxifloxacin, adds to QT prolongation. This raises the risk of torsades de pointes, especially in hospitalized patients with electrolyte disturbances.

How serious is the interaction between Erythromycin lactobionate and Moxifloxacin?

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 the combination and use an alternative antibiotic. If unavoidable, monitor ECG continuously or frequently and correct potassium and magnesium.

What other medicines interact with Moxifloxacin?

MediHelp also lists interactions of Moxifloxacin with, for example, Amiodarone, Arsenic trioxide, Disopyramide. The full list is on the Moxifloxacin page.

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