A gastroenterologist typically initiates the diagnostic process by conducting a physical examination. This may involve palpating and auscultating abdominal organs externally or performing a digital rectal examination. Follow-up investigations such as blood tests, stool tests, or imaging studies like GI X-rays may be ordered to gather additional information. However, when further insight is required, gastroenterologists are trained to perform endoscopic procedures. These involve utilizing an endoscope—a slender, flexible tube equipped with a miniature camera—to visualize internal structures.

Endoscopic procedures encompass:

• Upper endoscopy (EGD): Examination of the upper gastrointestinal (GI) tract, spanning from the throat to the upper small intestine (duodenum).
• Enteroscopy: Inspection of the small intestine.
• Colonoscopy: Evaluation of the lower GI tract or large intestine.
• Endoscopic ultrasound: Employing an ultrasound probe attached to the endoscope during upper or lower endoscopy to visualize the biliary system.
• ERCP (Endoscopic Retrograde Cholangiopancreatography): A procedure combining upper endoscopy with fluoroscopic X-rays to assess the bile ducts and pancreatic ducts.
• Polypectomy: Removal of polyps from the stomach or intestines during endoscopy.