Drug interactions
Erythromycin + Loperamide
Severity: Moderate
Erythromycin and Loperamide: moderate 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
Erythromycin raises loperamide plasma levels. At high doses loperamide causes QT prolongation and arrhythmias, and higher exposure also increases the risk of CNS effects.
What this interaction means in plain words
Erythromycin and Loperamide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Erythromycin belongs to Anti Bacterial; Loperamide belongs to Gastrointestinal Tract.
Why it happens
Erythromycin inhibits P-glycoprotein and CYP3A4, increasing loperamide absorption and central exposure.
What to do
Keep loperamide at labeled doses and avoid excessive use. Monitor for palpitations, dizziness or syncope, and obtain an ECG if symptoms occur.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Erythromycin
- Conivaptan + Erythromycin Contraindicated
- Dihydroergotamine intranasal + Erythromycin Contraindicated
- Dihydroergotamine + Erythromycin Contraindicated
- Domperidone + Erythromycin Contraindicated
- Dronedarone + Erythromycin Contraindicated
- Droperidol + Erythromycin Contraindicated
Other interactions of Loperamide
Frequently asked questions
Can I take Erythromycin with Loperamide?
MediHelp rates the interaction as moderate. Erythromycin and Loperamide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Erythromycin raises loperamide plasma levels. At high doses loperamide causes QT prolongation and arrhythmias, and higher exposure also increases the risk of CNS effects.
How serious is the interaction between Erythromycin and Loperamide?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Keep loperamide at labeled doses and avoid excessive use. Monitor for palpitations, dizziness or syncope, and obtain an ECG if symptoms occur.
What other medicines interact with Erythromycin?
MediHelp also lists interactions of Erythromycin with, for example, Conivaptan, Dihydroergotamine intranasal, Dihydroergotamine. The full list is on the Erythromycin page.
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