Drug interactions
Letermovir + Methadone
Severity: Moderate
Letermovir and Methadone: 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 inhibits CYP3A and may increase methadone levels, but it also induces CYP2C9 and CYP2C19, which contribute to methadone metabolism. Net effects on methadone are uncertain and could produce either excess opioid effect or reduced efficacy.
What this interaction means in plain words
Letermovir and Methadone 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 belongs to Anti Virals; Methadone belongs to Musculoskeletal.
Why it happens
Letermovir moderately inhibits CYP3A while inducing CYP2C9/2C19, giving an unpredictable net effect on methadone exposure.
What to do
Monitor for sedation, respiratory depression and withdrawal symptoms when starting or stopping letermovir. Adjust the methadone dose based on clinical response.
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 Methadone
- Alvimopan + Methadone Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Methadone Contraindicated
- Droperidol + Methadone Contraindicated
- Ibutilide + Methadone Contraindicated
- Isocarboxazid + Methadone Contraindicated
- Lefamulin + Methadone Contraindicated
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 Letermovir with Methadone?
MediHelp rates the interaction as moderate. Letermovir and Methadone 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 inhibits CYP3A and may increase methadone levels, but it also induces CYP2C9 and CYP2C19, which contribute to methadone metabolism. Net effects on methadone are uncertain and could produce either excess opioid effect or reduced efficacy.
How serious is the interaction between Letermovir and Methadone?
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 sedation, respiratory depression and withdrawal symptoms when starting or stopping letermovir. Adjust the methadone dose based on clinical response.
What other medicines interact with Methadone?
MediHelp also lists interactions of Methadone with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Droperidol. The full list is on the Methadone page.
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