Randomised trial, 1994
Does L-tryptophan help premenstrual mood symptoms?
In a small uncontrolled study, 13 women improved significantly on L-tryptophan with mild side effects, but because there was no placebo group, we cannot be sure the improvement came from treatment rather than from expectation of improvement. The evidence is weak.
What they did
Open pilot study with no control group. 13 women with late luteal phase dysphoric disorder (the older name for PMDD) had baseline symptom measurements during one cycle. They then took L-tryptophan 6 grams per day for the next three cycles.
What they found
L-tryptophan treatment was associated with significant improvement in symptoms including depression, irritability, insomnia, and carbohydrate craving, with only mild side effects.
What it means for you
L-tryptophan may help premenstrual mood symptoms, but this needs to be tested in a proper randomized controlled trial with placebo because without a control group, placebo effect could explain the improvement. The study is small and from 1994.
13
women studied
6 grams
daily dose of L-tryptophan
3 cycles
duration of treatment
About the study
- Original title
- Tryptophan in the treatment of late luteal phase dysphoric disorder: a pilot study
- Authors
- Steinberg S, Annable L, Young SN et al.
- Journal
- Journal of psychiatry & neuroscience : JPN
- Year
- 1994
- Study design
- Randomised trial
- What was tested
- L-tryptophan 6 grams per day
- Open access
- Yes
- Read the paper
- https://pubmed.ncbi.nlm.nih.gov/8204563/
Topics
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