Some patients may experience mild discomfort during the colonic irrigation procedure. This is due to the insertion of the tube into the anal canal. Some people feel like they need to go to the bathroom during or after the procedure. Others may have minor cramping. In rare cases, patients may even pass stool during the procedure.  With insertion of any type of foreign body into the rectum, there is a risk of causing trauma which can lead to bleeding or perforation (a hole in the bowel which can require surgical repair).