Drug interactions
Erythromycin base + Loperamide
Severity: Moderate
Erythromycin base 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 inhibits P-gp and CYP3A4 and can increase loperamide concentrations. Erythromycin also prolongs the QT interval, so the combination raises the risk of cardiac toxicity.
What this interaction means in plain words
Erythromycin base 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.
Why it happens
Inhibition of P-gp and CYP3A4 by erythromycin raises loperamide exposure, with additive QT effects.
What to do
Use loperamide at the lowest effective dose and avoid exceeding labeled limits. Monitor for palpitations, syncope and CNS depression, and check electrolytes if risk factors are present.
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 Loperamide
Frequently asked questions
Can I take Erythromycin base with Loperamide?
MediHelp rates the interaction as moderate. Erythromycin base 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 inhibits P-gp and CYP3A4 and can increase loperamide concentrations. Erythromycin also prolongs the QT interval, so the combination raises the risk of cardiac toxicity.
How serious is the interaction between Erythromycin base 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: Use loperamide at the lowest effective dose and avoid exceeding labeled limits. Monitor for palpitations, syncope and CNS depression, and check electrolytes if risk factors are present.
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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