Drug interactions
Methadone + Nirmatrelvir
Severity: Moderate
Methadone and Nirmatrelvir: 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
Nirmatrelvir is given with ritonavir, which can modify methadone exposure through opposing effects on CYP2B6 induction and CYP3A4 inhibition. The net effect is typically a modest reduction in methadone levels, and withdrawal or, in some cases, increased opioid effects can occur. The short five-day course limits the duration of any effect.
What this interaction means in plain words
Methadone and Nirmatrelvir 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.
Methadone belongs to Musculoskeletal; Nirmatrelvir belongs to Anti Virals.
Why it happens
Ritonavir-related CYP2B6 induction and CYP3A4 inhibition alter methadone clearance.
What to do
Monitor for withdrawal and sedation during and shortly after the course; adjust methadone only if clinically needed.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Methadone and Nirmatrelvir, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
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 Nirmatrelvir
- Alfuzosin + Nirmatrelvir Contraindicated
- Amiodarone + Nirmatrelvir Contraindicated
- Apalutamide + Nirmatrelvir Contraindicated
- Carbamazepine + Nirmatrelvir Contraindicated
- Colchicine + Nirmatrelvir Contraindicated
- Dronedarone + Nirmatrelvir Contraindicated
Frequently asked questions
Can I take Methadone with Nirmatrelvir?
MediHelp rates the interaction as moderate. Methadone and Nirmatrelvir 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. Nirmatrelvir is given with ritonavir, which can modify methadone exposure through opposing effects on CYP2B6 induction and CYP3A4 inhibition. The net effect is typically a modest reduction in methadone levels, and withdrawal or, in some cases, increased opioid effects can occur. The short five-day course limits the duration of any effect.
How serious is the interaction between Methadone and Nirmatrelvir?
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 withdrawal and sedation during and shortly after the course; adjust methadone only if clinically needed.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
