Drug interactions
L-tryptophan + Mirtazapine
Severity: Moderate
L-tryptophan and Mirtazapine: 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
L-tryptophan is a serotonin precursor, and combining it with serotonergic antidepressants has been associated with serotonin syndrome. Mirtazapine has a lower serotonergic risk than SSRIs, but additive effects remain possible, especially with higher tryptophan doses or other serotonergic drugs.
What this interaction means in plain words
L-tryptophan and Mirtazapine 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
Increased serotonin synthesis from tryptophan combined with mirtazapine's serotonergic activity produces additive serotonergic effects.
What to do
Monitor for agitation, tremor, hyperreflexia, sweating and diarrhea, and stop tryptophan if serotonin toxicity is suspected.
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?
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Other interactions of Mirtazapine
- Isocarboxazid + Mirtazapine Contraindicated
- Mirtazapine + Phenelzine Contraindicated
- Mirtazapine + Pimozide Contraindicated
- Mirtazapine + Procarbazine Contraindicated
- Mirtazapine + Rasagiline Contraindicated
- Mirtazapine + Selegiline Contraindicated
Frequently asked questions
Can I take L-tryptophan with Mirtazapine?
MediHelp rates the interaction as moderate. L-tryptophan and Mirtazapine 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. L-tryptophan is a serotonin precursor, and combining it with serotonergic antidepressants has been associated with serotonin syndrome. Mirtazapine has a lower serotonergic risk than SSRIs, but additive effects remain possible, especially with higher tryptophan doses or other serotonergic drugs.
How serious is the interaction between L-tryptophan and Mirtazapine?
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 agitation, tremor, hyperreflexia, sweating and diarrhea, and stop tryptophan if serotonin toxicity is suspected.
What other medicines interact with Mirtazapine?
MediHelp also lists interactions of Mirtazapine with, for example, Isocarboxazid, Phenelzine, Pimozide. The full list is on the Mirtazapine page.
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