Drug interactions
Loperamide + Trofinetide
Severity: Moderate
Loperamide and Trofinetide: 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
Trofinetide increases loperamide exposure, which can heighten opioid-type adverse effects such as constipation and, at high exposure, cardiac conduction abnormalities and CNS depression. Loperamide is a sensitive CYP3A and P-gp substrate.
What this interaction means in plain words
Loperamide and Trofinetide 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.
Loperamide belongs to Gastrointestinal Tract; Trofinetide belongs to Central Nervous System.
Why it happens
Trofinetide inhibits intestinal CYP3A and/or P-gp, raising loperamide concentrations.
What to do
Use the lowest effective loperamide dose and monitor for constipation, sedation and QT or arrhythmia symptoms. Note that trofinetide itself commonly causes diarrhea, so avoid overuse of loperamide.
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 Trofinetide
Other interactions of Loperamide
Frequently asked questions
Can I take Loperamide with Trofinetide?
MediHelp rates the interaction as moderate. Loperamide and Trofinetide 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. Trofinetide increases loperamide exposure, which can heighten opioid-type adverse effects such as constipation and, at high exposure, cardiac conduction abnormalities and CNS depression. Loperamide is a sensitive CYP3A and P-gp substrate.
How serious is the interaction between Loperamide and Trofinetide?
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 the lowest effective loperamide dose and monitor for constipation, sedation and QT or arrhythmia symptoms. Note that trofinetide itself commonly causes diarrhea, so avoid overuse of loperamide.
What other medicines interact with Trofinetide?
MediHelp also lists interactions of Trofinetide with, for example, Amlodipine-hydrochlorothiazide-valsartan, Amlodipine-olmesartan-hydrochlorothiazide, Amlodipine-olmesartan. The full list is on the Trofinetide page.
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