The clinical phase of the study comprises up to 2 weeks of screening for patient's eligibility, a 2-week run-in period , a 8-week double-blind treatment period, and a 4-week safety follow-up.~Patients report their IBS-related symptoms daily from run-in until end of treatment.
The aim of this study is to evaluate the efficacy and safety of Changkang granule as compared to placebo over a 8-week treatment period and explore TCM syndrome types.