Effects of Kamishoyosan, a Traditional Japanese Medicine, on Menopausal Symptoms: A Randomized, Placebo-Controlled, Double-Blind Clinical Trial

Objective. Kampo medicine, a traditional Japanese medicine, is widely used in Japan, especially in the field of menopause medicine. However, few studies have shown evidence-based effects. This study aimed to confirm the effects of kamishoyosan on menopausal symptoms with a randomized, placebo-controlled, double-blind clinical trial. Methods. Subjects were randomly allocated to groups that received either kamishoyosan (n = 101) or a placebo resembling kamishoyosan (n = 104). The primary outcomes were the change in the number of hot flashes, depression scores, improvements of anxiety, quality of life (QOL), and menopausal symptoms before and 4 and 8 weeks after initiation of treatment with the study drug. The secondary outcome was drug safety. Results. After 8 weeks, the number of hot flashes decreased after treatment in both groups, but there was no significant difference between the two groups. The changes in SDS scores showed the same results. Moreover, no significant differences were observed between the two groups in assessments with the STAI, SF-36, and JSOG menopausal index. No serious adverse effect was reported. Conclusions. This first placebo-controlled double-blind randomized trial with kamishoyosan demonstrated that it was safe and had some effects on climacteric symptoms, but not significant compared with placebo. Some problems, such as placebo effects, in the study of Kampo therapy for menopausal symptoms, were revealed. This trial is registered with the trial registration number. UMIN 000006042.