Drug interactions
Lefamulin + Loperamide
Severity: Major
Lefamulin and Loperamide: 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 agents can prolong the QT interval, so combined use may increase the risk of torsades de pointes, especially with electrolyte disturbance or heart disease. Oral lefamulin is also a CYP3A4 and P-gp substrate and inhibitor, which could raise loperamide levels.
What this interaction means in plain words
Lefamulin and Loperamide 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.
Lefamulin belongs to Anti Bacterial; Loperamide belongs to Gastrointestinal Tract.
Why it happens
Additive QT prolongation, with possible increase in loperamide exposure through CYP3A4 and P-gp inhibition.
What to do
Avoid the combination where possible, especially at high loperamide doses. If used, check ECG 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?
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Other interactions of Loperamide
Other interactions of Lefamulin
- Lefamulin + Methadone Contraindicated
- Lefamulin + Pimavanserin Contraindicated
- Lefamulin + Pimozide Contraindicated
- Lefamulin + Quinidine Contraindicated
- Alfuzosin + Lefamulin Major
- Amiodarone + Lefamulin Major
Frequently asked questions
Can I take Lefamulin with Loperamide?
MediHelp rates the interaction as major. Lefamulin and Loperamide 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 agents can prolong the QT interval, so combined use may increase the risk of torsades de pointes, especially with electrolyte disturbance or heart disease. Oral lefamulin is also a CYP3A4 and P-gp substrate and inhibitor, which could raise loperamide levels.
How serious is the interaction between Lefamulin and Loperamide?
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 where possible, especially at high loperamide doses. If used, check ECG and correct potassium and magnesium.
What other medicines interact with Loperamide?
MediHelp also lists interactions of Loperamide with, for example, Amiodarone, Amisulpride, Anagrelide. The full list is on the Loperamide page.
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