Review: poor quality studies suggest that vitamin B-6 is beneficial in premenstrual syndrome
QUESTION: Is vitamin B-6 (pyridoxine) effective for relieving overall premenstrual symptoms and depressive premenstrual symptoms?
Studies were identified by searching Medline (1966–98), EMBASE/Excerpta Medica (1988–96), PsycLIT (1974–97), CINAHL (1982–97), and the Cochrane Controlled Trials Register with the terms premenstrual syndrome, pyridoxine, PMT, LLPDD, and PMDD. Bibliographies of relevant articles were scanned, and pharmaceutical companies were contacted.
Published and unpublished studies in any language were selected if they were randomised, double blind, placebo controlled studies for which data could be acquired. Studies involving multivitamin supplements were included if the supplement contained ≥50 mg of vitamin B-6. Authors were contacted if additional information was required.
Data were extracted on participants, dose and preparation of vitamin B-6, outcome measures, results, withdrawals, side effects, and quality scores. Main outcome was subjective improvement in overall premenstrual symptoms, and a secondary outcome was improvement in depressive premenstrual symptoms. High quality studies had scores ≥3 on the Jadad scale (maximum 5 points) and ≥6 …