Prior to endoscopy you have to fast (no food or drink) for up to six hours. In the endoscopy room you are given an injection of a sedative drug (similar to Valium) into a vein in the arm. A blood sample may be taken from the vein at this time. Your throat is sprayed with a local anaesthetic spray. Then a narrow, flexible tube is inserted through your mouth. The tube is only about the thickness of your little finger and although most patients have a little discomfort during the first five seconds of the test, once the tube has passed the back of the throat, very little discomfort occurs. Through this tube (the endoscope), the doctor examines the inside of the oesophagus, stomach and duodenum. While in the stomach, it is usual to take up to ten small biopsy samples from the lining of the duodenum, stomach, and oesophagus.
The complete endoscopy examination takes about 15 minutes. After the test you can not drive a car for the remainder of the day because you may be drowsy. It is also illegal to drive after taking sedative drugs.