An upper endoscopy is used to directly view the esophagus, stomach, and first part of the small bowel.  We do this in order to evaluate stomach pain or swallowing difficulties.  
In order to make this comfortable for the patient, we use two types of sedation as well as a topical numbing spray on the back of the throat.  
Once in the GI tract, we can take biopsies if there are abnormalities.