A gastroenterologist is a doctor who specializes in treating diseases and conditions related to the gastrointestinal (GI) tract and digestive system. The GI tract includes the oesophagus, stomach, small intestine, large intestine, rectum, gallbladder, pancreas, and liver. Gastroenterologists complete advanced training beyond medical school to become experts on the complicated digestive system. They must first complete a three-year internal medicine…