Efficacy and safety of herbal medicine (Dangguijagyag-san) for primary dysmenorrhea: study protocol for a randomized, double-blind, placebo-controlled, parallel-group, multi-center trial

摘要

Background: Dangguijagyag-san, also known as Dangguishaoyao-san in Chinese and Toki-shakuyakui-san in Japanese, has been frequently used to treat symptoms associated with dysmenorrhea. The purpose of this trial is to evaluate the efficacy and safety of the herbal medicine, Dangguijagyag-san, relative to those of active control, Gamisoyo-san, and a placebo control for primary dysmenorrhea.