Efficacy of vitamin B-6 in the treatment of premenstrual syndrome: systematic review.

OBJECTIVE To evaluate the efficacy of vitamin B-6 in the treatment of premenstrual syndrome. DESIGN Systematic review of published and unpublished randomised placebo controlled trials of the effectiveness of vitamin B-6 in the management of premenstrual syndrome. SUBJECTS 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. RESULTS 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. CONCLUSION 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.