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Drug interactions

Gemifloxacin + Methadone

Severity: Major

Gemifloxacin and Methadone: 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

Both drugs prolong the QTc interval, so their combination increases the risk of torsades de pointes and sudden cardiac death. The risk is higher with electrolyte disturbances, heart disease or high methadone doses.

What this interaction means in plain words

Gemifloxacin and Methadone 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.

Gemifloxacin belongs to Anti Bacterial; Methadone belongs to Musculoskeletal.

Evidence level: Moderate

Why it happens

Additive blockade of cardiac hERG potassium channels leading to QT prolongation.

What to do

Prefer a non-QT-prolonging antibiotic. If unavoidable, check the ECG and electrolytes and monitor the QTc during therapy.

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 Gemifloxacin with Methadone?

MediHelp rates the interaction as major. Gemifloxacin and Methadone 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. Both drugs prolong the QTc interval, so their combination increases the risk of torsades de pointes and sudden cardiac death. The risk is higher with electrolyte disturbances, heart disease or high methadone doses.

How serious is the interaction between Gemifloxacin and Methadone?

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 unavoidable, check the ECG and electrolytes and monitor the QTc during therapy.

What other medicines interact with Methadone?

MediHelp also lists interactions of Methadone with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Droperidol. The full list is on the Methadone page.

Full monographs, dosing and an interaction checker in the MediHelp app

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