Upper GI endoscopy, also known as esophagogastroduodenoscopy (EGD), is a minimally invasive procedure used to examine the upper gastrointestinal tract. During the procedure, a flexible tube with a light and camera attached (endoscope) is inserted through the mouth and gently guided down the esophagus, stomach, and into the beginning of the small intestine. This allows the doctor to visually inspect the lining of the esophagus, stomach, and duodenum for abnormalities such as inflammation, ulcers, tumors, or bleeding. Upper GI endoscopy is commonly performed to investigate symptoms like difficulty swallowing, persistent heartburn, abdominal pain, nausea, or unexplained weight loss. It may also be used to collect tissue samples (biopsy) for further examination or to treat certain conditions, such as removing polyps or stopping bleeding using specialized instruments inserted through the endoscope. The procedure is typically done under sedation to ensure patient comfort. Afterward, patients may experience temporary throat discomfort but can usually resume normal activities shortly thereafter.