Anti-irritable Bowel Syndrome Syrup Improves Constipation-Predominant Irritable Bowel Syndrome: A Randomized, Placebo-Controlled Trial

Objective: To evaluate the efficacy and safety of administration of the formulated Persian herbal syrup on improving the symptoms of patients with constipation-predominant irritable bowel syndrome(IBS-C). Methods: This study was conducted in 70 patients with IBS-C, who were recruited from 3 medical centers in Mashhad, Iran, from November 2017 to August 2018. Seventy patients were randomly assigned to 2 groups including treatment and placebo groups by block randomization, 35 cases in each group. Patients in the treatment group received 15 m L of anti-IBS syrup, thrice daily for 6 weeks and followed up for 4 weeks. Placebo syrup was also prepared through similar instruction, BP syrup without plant extract was used. Primary outcome induding IBS Symptom Severity Scale(IBS-SSS) questionnaire and secondary outcomes in terms of Hospital Anxiety and Depression(HADS) questionnaires, the Bristol Stool Form Scale(BSFS) were completed and evaluated at weeks 6 and 10, respectively. Safety indices were collected at the end of the treatment and Common Terminology Criteria for Adverse Events v4.0(CTCAE) was used to evaluate the adverse events. Results: The response to treatment was 84.4%(27/32) in the treatment group and 46.4%(13/28) in the placebo group, respectively(P= 0.002). Compared with pre-treatment, a significant decrease was found on the IBS-SSS and BSFS scores after 6-week intervention in both groups(P<0.001). Moreover, IBS-SSS and BSFS scores in the treatment group were lower than the placebo group after the intervention(P=0.041). There was no significant difference in the anxiety and depression scores after treatment in both groups(P>0.05). Side effects reported in the treatment group included 2 cases of headache during the first week of the onset of the treatment, 1 case of drowsiness, 1 case of increase in menstrual bleeding, which did not result in discontinuation of the treatment. In the placebo group, 1 case of exacerbation of the disease was reported. Conclusions: Anti-IBS syrup significantly reduced the severity of IBS symptoms compared to placebo. However, there was a need for further investigation regarding the anxiety and depression scores.