Drug interactions
Erlotinib + Letermovir
Severity: Moderate
Erlotinib and Letermovir: 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
Letermovir is a moderate CYP3A inhibitor and may increase erlotinib concentrations, raising the risk of adverse effects.
What this interaction means in plain words
Erlotinib and Letermovir 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.
Erlotinib belongs to Oncology; Letermovir belongs to Anti Virals.
Why it happens
Letermovir inhibits CYP3A4, reducing erlotinib clearance.
What to do
Monitor for erlotinib toxicity such as diarrhea and rash during letermovir prophylaxis. Reduce the erlotinib dose if severe reactions develop.
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 Erlotinib
- Amobarbital + Erlotinib Major
- Apalutamide + Erlotinib Major
- Carbamazepine + Erlotinib Major
- Cobicistat + Erlotinib Major
- Darunavir + Erlotinib Major
- Dexlansoprazole + Erlotinib Major
Other interactions of Letermovir
- Ergotamine + Letermovir Contraindicated
- Letermovir + Pimozide Contraindicated
- Apalutamide + Letermovir Major
- Atorvastatin + Letermovir Major
- Carbamazepine + Letermovir Major
- Colchicine + Letermovir Major
Frequently asked questions
Can I take Erlotinib with Letermovir?
MediHelp rates the interaction as moderate. Erlotinib and Letermovir 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. Letermovir is a moderate CYP3A inhibitor and may increase erlotinib concentrations, raising the risk of adverse effects.
How serious is the interaction between Erlotinib and Letermovir?
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 for erlotinib toxicity such as diarrhea and rash during letermovir prophylaxis. Reduce the erlotinib dose if severe reactions develop.
What other medicines interact with Erlotinib?
MediHelp also lists interactions of Erlotinib with, for example, Amobarbital, Apalutamide, Carbamazepine. The full list is on the Erlotinib page.
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