I did four flushes without any post flush colon cleansing. After number 4 I started to have pain in my abdomen, and started to feel sick, then sicker. I asked Andreas about it, and he suggested it was a stuck stone, recommending a colonic or colemas. I was too embarressed though, and chose to take some castor oil every day to dry and flush the stones out. after a few weeks I passed it, and it was huge. I almost passed out. It took weeks for the toxic feeling to go away. Finally I broke down and got a colonic, and it opened my eyes because it made me feel so much better. I did one more colonic then bought a home colema system. Now I don't mess around, I always do a pre and post flush colema and wouldn't think about doing it any other way.