Drug interactions
L-tryptophan + Trazodone
Severity: Major
L-tryptophan and Trazodone: major 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
L-tryptophan is a serotonin precursor and, with a serotonergic antidepressant like trazodone, may cause serotonin toxicity. Reported features include agitation, tremor, diarrhea, sweating and hyperthermia.
What this interaction means in plain words
L-tryptophan and Trazodone 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
Increased serotonin synthesis from tryptophan combined with trazodone's serotonergic activity.
What to do
Avoid the combination where possible, or use low doses with monitoring for serotonin syndrome. Stop tryptophan if symptoms develop.
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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Other interactions of Trazodone
- Arsenic trioxide + Trazodone Contraindicated
- Ibutilide + Trazodone Contraindicated
- Isocarboxazid + Trazodone Contraindicated
- Levoketoconazole + Trazodone Contraindicated
- Methylene blue + Trazodone Contraindicated
- Phenelzine + Trazodone Contraindicated
Frequently asked questions
Can I take L-tryptophan with Trazodone?
MediHelp rates the interaction as major. L-tryptophan and Trazodone 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. L-tryptophan is a serotonin precursor and, with a serotonergic antidepressant like trazodone, may cause serotonin toxicity. Reported features include agitation, tremor, diarrhea, sweating and hyperthermia.
How serious is the interaction between L-tryptophan and Trazodone?
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 the combination where possible, or use low doses with monitoring for serotonin syndrome. Stop tryptophan if symptoms develop.
What other medicines interact with Trazodone?
MediHelp also lists interactions of Trazodone with, for example, Arsenic trioxide, Ibutilide, Isocarboxazid. The full list is on the Trazodone page.
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