I tried Colonics when I needed to prep for a colonoscopy. I chose a certified salon and was impressed with the privacy and ease of use. There was some cramping, but after doing a package of 3, the water ran clear and I felt better. Unfortunately, according to the arrogant doctor, since I "didn't prep the way he wanted me to" because I have severe volume depletion, he failed to complete the procedure and black listed me as "poor prep" when I actually had "over-prepped" including being on a liquid diet for a week. Anyway, the experience of the colonic was worth it because I suffer from chronic constipation.