Overview: The Basics
its tip, called an endoscope, to look inside the upper digestive system of the esophagus, stomach and
the first part of the small intestine. The endoscope is passed through the mouth and down the throat
to the esophagus. It may also have a small biopsy instrument to remove tissue that is then checked
under a microscope for abnormalities.
What to Expect: During the Screening
You will be given a sedative, and a local anesthetic may be sprayed into your mouth to suppress
the gag reflex when the endoscope is inserted. A mouth guard will be inserted to protect your teeth
as well as the endoscope. Dentures must be removed.
In most cases, an intravenous line will be inserted into the arm to administer the sedation and any
medications that might be needed. You will lie on your left side, and, after the sedative has taken
effect, the endoscope will be gently guided through the esophagus to the stomach and the beginning
of the small intestine. Air will be introduced through the endoscope to enhance viewing. The lining of
the esophagus, stomach and upper small intestine is examined, and biopsies can be performed at the
After the test is complete, food and liquids will be restricted to prevent choking until the anesthetic
wears off and the gag reflex returns.
The actual test lasts about 10 to 20 minutes. There may be a sensation of gas after the procedure.
Biopsies cannot be felt. Because of the intravenous sedation, you likely will not feel any discomfort and
may have no memory of the test.
What can be found?
An upper endoscopy can help determine causes for heartburn, the presence of hiatal hernias, the
cause of abdominal pain, unexplained anemia, and the cause of swallowing difficulties, upper GI bleeding,
and the presence of tumors or ulcers.
How to Prepare
The stomach must be empty for the procedure to be thorough and safe, so you must fast about
6-12 hours before the test. You may also be told to stop aspirin and other blood-thinning medications
for several days before the test. You should also arrange for someone to take you home because of
the sedation during the procedure. Your physician may give other special instructions.