Drug interactions
Aprepitant + Lapatinib
Severity: Moderate
Aprepitant and Lapatinib: 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
Aprepitant is a moderate CYP3A4 inhibitor and lapatinib is a CYP3A4 substrate, so lapatinib concentrations may rise. This could increase the risk of lapatinib toxicity including QT prolongation, diarrhea and hepatotoxicity.
What this interaction means in plain words
Aprepitant and Lapatinib 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.
Aprepitant belongs to Gastrointestinal Tract; Lapatinib belongs to Oncology.
Why it happens
Aprepitant inhibits CYP3A4-mediated metabolism of lapatinib.
What to do
Monitor ECG and electrolytes, and watch for diarrhea and liver test changes; consider a lapatinib dose reduction if toxicity develops, especially with multi-day aprepitant regimens.
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 Aprepitant
- Aprepitant + Lomitapide Contraindicated
- Aprepitant + Pimozide Contraindicated
- Aprepitant + Avapritinib Major
- Aprepitant + Bosutinib Major
- Aprepitant + Carbamazepine Major
- Aprepitant + Cobicistat Major
Other interactions of Lapatinib
- Dofetilide + Lapatinib Contraindicated
- Ibutilide + Lapatinib Contraindicated
- Lapatinib + Pimozide Contraindicated
- Lapatinib + Saquinavir Contraindicated
- Lapatinib + Thioridazine Contraindicated
- Adagrasib + Lapatinib Major
Frequently asked questions
Can I take Aprepitant with Lapatinib?
MediHelp rates the interaction as moderate. Aprepitant and Lapatinib 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. Aprepitant is a moderate CYP3A4 inhibitor and lapatinib is a CYP3A4 substrate, so lapatinib concentrations may rise. This could increase the risk of lapatinib toxicity including QT prolongation, diarrhea and hepatotoxicity.
How serious is the interaction between Aprepitant and Lapatinib?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor ECG and electrolytes, and watch for diarrhea and liver test changes; consider a lapatinib dose reduction if toxicity develops, especially with multi-day aprepitant regimens.
What other medicines interact with Aprepitant?
MediHelp also lists interactions of Aprepitant with, for example, Lomitapide, Pimozide, Avapritinib. The full list is on the Aprepitant page.
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