Long term management of chronic digestive diseases like gastroesophageal reflux, ulcers, Crohn. s disease and ulcerative colitis, require far more than prescription drugs. John Mizenko, DO, a holistic gastroenterologist, believes it is essential to understand a patient. s eating habits, psychosocial stresses, and the subjective meaning of the symptoms. He offers his strategies, learned over 40 years in practice, for treating a range of common digestive diseases.