An upper endoscopy is a procedure a doctor uses to look at the inner lining of the upper digestive tract (the esophagus, stomach, and duodenum, which is the first part of the small intestine).

This test is also sometimes called an esophagogastroduodenoscopy, or EGD.

This procedure is done with an endoscope, a thin, flexible tube with a light and a small video camera on the end. The tube is put in through your mouth, down your throat, and into your esophagus, stomach, and small intestine.