EFFECT OF KETOTIFEN ON ABDOMINAL SYMPTOMS, VISCERAL SENSITIVITY AND INTESTINAL MAST CELL IN PATIENTS WITH IRRITABLE BOWEL SYNDROME WITH DIARRHEAL

Aim: To investigate the effects of ketotifen on abdominal symptoms, visceral sensitivity and intestinal mast cells in patients with irritable bowel syndrome with diarrhea (IBS-D). Methods: Patients with IBS-D were randomly divided into ketotifen group and placebo group, the ketotifen group were oral administration of ketotifen tablets, 1mg, bid for 8 weeks, the control group were received oral placebo for 8 weeks. Gastrointestinal symptoms evaluation scale questionnaire, anorectal sensory function, the number and activity status of mast cell (MC) were measured before and 8 weeks after treatment in these two group. Results: (1) A total of 87 IBS-D patients were included, 44 in ketotifen group and 43 in control group, there was no significant difference in age and sex between the two groups. (2)Total effective rate of improvement of abdominal symptoms in ketotifen group was significantly higher than that in control group(72.7% vs. 34.9%, P<0.001). (3) Compared with before treatment, first sensation, urge to defecation, discomfort/pain sensory thresholds of ketotifen group were significantly increased after treatment (P<0.05), no significant changes were observed in the control group (P>0.05); (4) Compared with before treatment, The number of MC in terminal ileum, the proportion of MC degranulation state in the terminal ileum, ascending colon, sigmoid colon in ketotifen group were significantly decreased after treatment (P<0.05), there was no significant change in the number of MC and the proportion of degranulation state in the control group (P>0.05); (5) 5 patients (11.4%) in ketotifen group adverse reactions, mainly manifested as feeling of drowsiness or fatigue, which disappeared after taking the drug one week. Conclusion: Ketotifen can significantly relieve the abdominal symptoms and improve the visceral sensitivity of patients with IBS-D, which is closely related to it's effect on reduce the number and activity of MC in intestinal mucosa, especially the terminal ileum. [Figure presented]