To evaluate the efficacy of vitamin B-6 in the treatment of premenstrual syndrome.
Systematic review of published and unpublished randomised placebo controlled trials of the effectiveness of vitamin B-6 in the management of premenstrual syndrome.
Nine published trials representing 940 patients with premenstrual syndrome.
Main outcome measures
Proportion of women whose overall premenstrual symptoms showed an improvement over placebo. A secondary analysis was performed on the proportion of women whose premenstrual depressive symptoms showed an improvement over placebo.
Odds ratio relative to placebo for an improvement in overall premenstrual symptoms was 2.32 (95% confidence interval 1.95 to 2.54). Odds ratio relative to placebo for an improvement in depressive symptoms was 1.69 (1.39 to 2.06) from four trials representing 541 patients.
Conclusions are limited by the low quality of most of the trials included. Results suggest that doses of vitamin B-6 up to 100 mg/day are likely to be of benefit in treating premenstrual symptoms and premenstrual depression.
- Randomised placebo controlled studies of vitamin B-6 treatment for premenstrual symptoms were of insufficient quality to draw definitive conclusions
- Limited evidence exists to suggest that 100 mg of vitamin B-6 daily (and possibly 50 mg) are likely to be beneficial in the management of premenstrual syndrome
- Vitamin B-6 was significantly better than placebo in relieving overall premenstrual symptoms and in relieving depression associated with premenstrual syndrome, but the response was not dose dependent
- No conclusive evidence was found of neurological side effects with these doses
- A randomised controlled trial of sufficient power and quality is needed to compare vitamin B-6 with placebo to establish definitive recommendations for treatment