Drug interactions
Methadone + Methylene blue
Severity: Major
Methadone and Methylene blue: major interaction.
Last updated Sources: US FDA label
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
Methylene blue inhibits MAO-A and combined with methadone, which has serotonergic activity, can cause serotonin syndrome. Features include agitation, hyperthermia, tremor, clonus and autonomic instability.
What this interaction means in plain words
Methadone and Methylene blue can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Methylene blue inhibits monoamine oxidase A, adding to serotonergic effects of methadone.
What to do
Avoid if possible, using an alternative to methylene blue or a non-serotonergic opioid. If necessary, monitor closely for serotonin syndrome and stop the drugs if it develops.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
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 Methadone with Methylene blue?
MediHelp rates the interaction as major. Methadone and Methylene blue can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Methylene blue inhibits MAO-A and combined with methadone, which has serotonergic activity, can cause serotonin syndrome. Features include agitation, hyperthermia, tremor, clonus and autonomic instability.
How serious is the interaction between Methadone and Methylene blue?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid if possible, using an alternative to methylene blue or a non-serotonergic opioid. If necessary, monitor closely for serotonin syndrome and stop the drugs if it develops.
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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