Tryptophan (L-tryptophan)
What it is
An essential amino acid and direct precursor to serotonin and melatonin. Multiple trials show 1 to 3 grams before bed modestly improves sleep onset. Was pulled from the US market in 1989 after a contaminated batch caused eosinophilia-myalgia syndrome, killing 37 people. Modern manufacturing is safe, but the incident led many to prefer 5-HTP instead. Same serotonin syndrome risk as 5-HTP when combined with antidepressants.
Dose
500–2,000 mg before bed for sleep; NEVER combine with SSRIs, SNRIs, or MAOIs — serotonin syndrome risk
Time of day & tips
Take on an empty stomach 30–60 min before bed with water (not protein). NEVER combine with SSRIs, SNRIs, or MAOIs — risk of serotonin syndrome. Avoid combining with 5-HTP.
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