Before an endoscopy procedure begins, a sedative is administered to the patient to minimize gagging and discomfort. A plastic mouthguard is used to keep the mouth open, and an anesthetic spray is applied to the back of the throat to numb it. The endoscope is then gently inserted into the mouth. Your doctor may ask you to swallow as the endoscope passes down your throat. You might experience a sensation of pressure in the throat, but significant pain is usually not felt. Once the endoscope has passed the throat, the patient will be unable to speak, but can still make sounds. Endoscopy does not obstruct breathing. During the procedure, images are transmitted to a screen in the examination room. These scanning images of your digestive system are recorded for later review and analysis. To facilitate better visualization, a small amount of air pressure may be introduced into the esophagus, which helps expand the digestive tract. This allows the endoscope to move freely and makes it easier to examine the folds of the digestive system. You may feel a sensation of pressure or fullness from the added air. Special surgical instruments can be passed through the endoscope to take tissue samples (biopsies) or remove polyps. Once the examination is complete, the endoscope is gently and slowly withdrawn from your mouth.