Drug interactions
Asenapine transdermal + Methadone
Severity: Moderate
Asenapine transdermal 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
Asenapine has a modest QT-prolonging effect and methadone is a known QT-prolonging opioid. Together they may raise the risk of arrhythmia, and both add to sedation.
What this interaction means in plain words
Asenapine transdermal 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.
Why it happens
Additive QT prolongation and additive CNS depression.
What to do
Obtain a baseline ECG and monitor QTc and electrolytes, particularly in patients on higher methadone doses. Consider an alternative antipsychotic if QTc lengthens substantially.
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 Asenapine transdermal and Methadone, 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
Frequently asked questions
Can I take Asenapine transdermal with Methadone?
MediHelp rates the interaction as moderate. Asenapine transdermal 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. Asenapine has a modest QT-prolonging effect and methadone is a known QT-prolonging opioid. Together they may raise the risk of arrhythmia, and both add to sedation.
How serious is the interaction between Asenapine transdermal 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: Obtain a baseline ECG and monitor QTc and electrolytes, particularly in patients on higher methadone doses. Consider an alternative antipsychotic if QTc lengthens substantially.
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.
