Colon hydrotherapy, also referred to as a colonic, is an internal bath that helps cleanse the colon of toxins, gas, and accumulated fecal matter. Unlike an enema, it does not involve the retention of water, just a steady gentle flow in and out of the colon. At the same time, abdominal work is given to stimulate the colon to recover its natural shape, tone, and peristaltic wave action.