Drug interactions
Lefamulin + Methadone
Severity: Contraindicated
Lefamulin and Methadone: contraindicated 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
Lefamulin is a CYP3A4 inhibitor and itself prolongs the QT interval, and methadone is a CYP3A4 substrate with QT risk. The combination can raise methadone levels and increase the risk of torsades de pointes.
What this interaction means in plain words
Lefamulin and Methadone are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two.
Lefamulin belongs to Anti Bacterial; Methadone belongs to Musculoskeletal.
Why it happens
CYP3A4 inhibition by lefamulin increases methadone exposure, with additive QT prolongation.
What to do
Avoid lefamulin with methadone, particularly oral lefamulin, and choose an alternative antibiotic. If unavoidable, monitor ECG and for opioid toxicity.
What to ask your pharmacist
- Is there an alternative to one of these two medicines for me?
- If both are essential, who is monitoring me and how often?
- Which symptoms mean I should stop and seek help straight away?
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Other interactions of Methadone
- Alvimopan + Methadone Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Methadone Contraindicated
- Droperidol + Methadone Contraindicated
- Ibutilide + Methadone Contraindicated
- Isocarboxazid + Methadone Contraindicated
- Levoketoconazole + Methadone Contraindicated
Other interactions of Lefamulin
- Lefamulin + Pimavanserin Contraindicated
- Lefamulin + Pimozide Contraindicated
- Lefamulin + Quinidine Contraindicated
- Alfuzosin + Lefamulin Major
- Amiodarone + Lefamulin Major
- Amisulpride + Lefamulin Major
Frequently asked questions
Can I take Lefamulin with Methadone?
MediHelp rates the interaction as contraindicated. Lefamulin and Methadone are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two. Lefamulin is a CYP3A4 inhibitor and itself prolongs the QT interval, and methadone is a CYP3A4 substrate with QT risk. The combination can raise methadone levels and increase the risk of torsades de pointes.
How serious is the interaction between Lefamulin and Methadone?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid lefamulin with methadone, particularly oral lefamulin, and choose an alternative antibiotic. If unavoidable, monitor ECG and for opioid toxicity.
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.
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