If you’ve been plagued by tummy trouble, a gastroenterologist can help you feel better again. These doctors are specially trained to diagnose and treat problems with the gastrointestinal tract — the stomach, bowels, liver, pancreas and rectum. Gastroenterologists provide expert care for patients suffering with the pain of Crohn’s disease, irritable bowel syndrome (IBS) and celiac disease. They also perform endoscopic procedures to detect colon polyps and cancer.