Drug interactions
Methylene blue + Sumatriptan
Severity: Major
Methylene blue and Sumatriptan: 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 monoamine oxidase A, which metabolizes sumatriptan and serotonin. Combined use can raise serotonin levels and sumatriptan exposure, causing serotonin syndrome, which may be severe.
What this interaction means in plain words
Methylene blue and Sumatriptan 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
Inhibition of MAO-A by methylene blue, which increases serotonin and reduces sumatriptan metabolism.
What to do
Avoid giving them together; if methylene blue is urgently needed, stop sumatriptan and monitor for serotonin toxicity for up to 2 weeks or until 24 hours after the last methylene blue dose, whichever comes first.
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 Sumatriptan
- Almotriptan + Sumatriptan Contraindicated
- Dihydroergotamine intranasal + Sumatriptan Contraindicated
- Dihydroergotamine + Sumatriptan Contraindicated
- Eletriptan + Sumatriptan Contraindicated
- Ergoloid mesylates + Sumatriptan Contraindicated
- Ergotamine + Sumatriptan Contraindicated
Frequently asked questions
Can I take Methylene blue with Sumatriptan?
MediHelp rates the interaction as major. Methylene blue and Sumatriptan 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 monoamine oxidase A, which metabolizes sumatriptan and serotonin. Combined use can raise serotonin levels and sumatriptan exposure, causing serotonin syndrome, which may be severe.
How serious is the interaction between Methylene blue and Sumatriptan?
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 giving them together; if methylene blue is urgently needed, stop sumatriptan and monitor for serotonin toxicity for up to 2 weeks or until 24 hours after the last methylene blue dose, whichever comes first.
What other medicines interact with Sumatriptan?
MediHelp also lists interactions of Sumatriptan with, for example, Almotriptan, Dihydroergotamine intranasal, Dihydroergotamine. The full list is on the Sumatriptan page.
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