Gastroenterology (MeSH heading)is the branch of medicine focused on the digestive system and its disorders.

Diseases affecting the gastrointestinal tract, which include the organs from mouth to anus, along the alimentary canal, are the focus of this speciality. Physicians practicing in this field are called gastroenterologists. They have usually completed about eight years of pre-medical and medical education, a year-long internship (if this is not a part of the residency), three years of an internal medicine residency, and two to three years in the gastroenterology fellowship. Gastroenterologists perform a number of diagnostic and therapeutic procedures including colonoscopy, endoscopy, endoscopic retrograde cholangiancreatography (ERCP), endoscopic ultrasound and liver biopsy. Some gastroenterology trainees will complete a "fourth-year" (although this is often their seventh year of graduate medical education) in transplant hepatology, advanced endoscopy, inflammatory bowel disease, motility or other topics.

Hepatology, or hepatobiliary medicine, encompasses the study of the liver, pancreas, and biliary tree, while proctology emcompasses the fields of anus and rectum diseases. They are traditionally considered sub-specialties of gastroenterology.

What is a Gastroenterologist?

A Gastroenterologist is a physician with dedicated training and unique experience in the management of diseases of the gastrointestinal tract and liver. What is Gastroenterology? Gastroenterology is the study of the normal function and diseases of the esophagus, stomach, small intestine, colon and rectum, pancreas, gallbladder, bile ducts and liver. It involves a detailed understanding of the normal action (physiology) of the gastrointestinal organs including the movement of material through the stomach and intestine (motility), the digestion and absorption of nutrients into the body, removal of waste from the system, and the function of the liver as a digestive organ. It includes common and important conditions such as colon polyps and cancer, hepatitis, gastroesophageal reflux (heartburn), peptic ulcer disease, colitis, gallbladder and biliary tract disease, nutritional problems, Irritable Bowel Syndrome (IBS), and pancreatitis. In essence, all normal activity and disease of the digestive organs are part of the study of Gastroenterology.