BACKGROUND This study aimed to assess the efficacy and safety of drotaverine hydrochloride (DHC) in Chinese patients with irritable bowel syndrome (IBS). METHODS Totally, 144 patients with IBS were included and randomly divided into treatment group and placebo group in a 1:1 ratio. Patients received either DHC or placebo 80-mg tablet, 3 times daily for a total of 4 weeks. The primary outcome ...