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Drug interactions

Levofloxacin + Moxifloxacin

Severity: Major

Levofloxacin and Moxifloxacin: major interaction.

Last updated

Levofloxacin + Moxifloxacin | MediHelp

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

These are two fluoroquinolones with no rational reason for concurrent use, and both prolong the QT interval. Using them together adds arrhythmia risk without therapeutic benefit.

What this interaction means in plain words

Levofloxacin 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.

Levofloxacin belongs to Anti Bacterial; Moxifloxacin belongs to Anti Bacterial.

Evidence level: Moderate

Why it happens

Additive hERG potassium channel blockade; therapeutic duplication within the same class.

What to do

Avoid combining; use a single fluoroquinolone only if one is indicated. If an accidental overlap occurs, stop one agent and monitor the 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?

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

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Frequently asked questions

Can I take Levofloxacin with Moxifloxacin?

MediHelp rates the interaction as major. Levofloxacin 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. These are two fluoroquinolones with no rational reason for concurrent use, and both prolong the QT interval. Using them together adds arrhythmia risk without therapeutic benefit.

How serious is the interaction between Levofloxacin 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 combining; use a single fluoroquinolone only if one is indicated. If an accidental overlap occurs, stop one agent and monitor the ECG.

What other medicines interact with Levofloxacin?

MediHelp also lists interactions of Levofloxacin with, for example, Dronedarone, Ibutilide, Thioridazine. The full list is on the Levofloxacin page.

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