Gastroenterologists work in management and treatment of disorders associated with the digestive organs, including the stomach, bowel, liver and gall bladder. Abdominal pain, ulcers, diarrhea, rectal bleeding, cancer and jaundice are also treated. Lighted scopes are used to see internal organs for diagnostic and therapeutic procedures. Gastroenterologists often provide consultation with surgeons when abdominal operations are indicated. Gastroenterology is a sub-specialty of internal medicine.