Objectives:  To assess therapeutic effect of an extract of Vitex agnus castus (VAC, BNO 1095) in premenstrual syndrome (PMS) in Chinese women.
Design:  It was a prospective, randomised, double‐blind, placebo‐controlled study carried out in China. Eligible patients were treated with VAC extract or placebo for three cycles. Symptoms were documented with PMS diary (PMSD), a daily rating scale with 17 items. Main efficacy variable was the reduction percentage of 17 symptom score documented in PMSD during the luteal phase of the third treatment cycle.
Results:  A total of 67 patients were enrolled and randomly assigned to VAC group or placebo group. Of these, 64 patients completed the study (31 vs. 33). All the 17 symptoms showed a significantly greater improvement with VAC than placebo (P < 0.05) except lower abdominal cramping (P > 0.05).
Conclusion:  Vitex agnus castus is more effective than placebo in the treatment of moderate‐to‐severe PMS in Chinese women, especially in symptoms of negative effect and insomnia.