An upper GI and small bowel series is a set of x-rays taken to examine the esophagus, stomach, and small intestine. X-rays are taken after the patient has swallowed a barium suspension (contrast medium). See also barium enema (lower GI series).

X-rays are a form of electromagnetic radiation like light, but of higher energy, so they can penetrate the body to form an image on film. Structures that are dense (such as bone) will appear white, air will be black, and other structures will be shades of gray. Barium is very dense and will appear white on the x-ray film.

This test may be done in an office or in a hospital radiology department. You will be sitting or standing up while your heart, lungs, and abdomen are examined with a fluoroscope (a type of x-ray that projects images onto a monitor like a TV screen).

You may be given an injection of a medication that will temporarily slow bowel movement, so structures can be more easily imaged. You will then be given a drink like a milkshake that has a barium mixture in it. You must drink 16 - 20 oz. for the examination.

The passage of the barium through the esophagus, stomach, and small intestine is monitored on the fluoroscope. Pictures are taken with you in a variety of positions. The test usually takes around three hours. However, in some cases, it may take up to 6 hours to complete.

A GI series may include this test or a barium enema.

You may be given a restricted diet for 2 or 3 days before the test. You will likely be told not to smoke or eat for a period of time before the test. Generally, oral medications may be taken.

Be sure to check with your health care provider regarding any dietary or medication restrictions before the test. Never discontinue or decrease medications without consulting your health care provider.

Remove all jewelry before the test.

The x-ray causes no discomfort. The barium milkshake has a chalky texture.

The purpose of the test is to detect anatomic or functional abnormalities of the esophagus, stomach, and small intestine.

The esophagus, stomach, and small intestine are normal in size and contour.

• In the esophagus, abnormal results may mean:
  • Esophageal cancer
  • Benign esophageal stricture
  • Hiatal hernia (a portion of the stomach protrudes through the esophageal opening)
  • Diverticula (pouch-like sacs that protrude from the walls of an organ)
  • Ulcers (open sores)
  • Achalasia (esophagus fails to relax)
• In the stomach, abnormal results may mean:
  • Gastric cancer
  • Benign gastric ulcer
  • Polyps (a tumor that is usually noncancerous that grows on the mucous membrane)
  • Gastritis (inflammation of the stomach)
  • Pyloric stenosis (a narrowing of the opening from the stomach)
• In the small intestines the test may reveal:
  • Tumors
  • Malabsorption syndrome (inadequate absorption of nutrients in the intestinal tract)
  • Inflammation of the small intestines

• Alcoholic neuropathy
• Annular pancreas
• CMV gastroenteritis/colitis
• Cystic fibrosis
• Duodenal ulcer
• Gastroesophageal reflux disease
• Gastroparesis
• Intestinal obstruction
• Lower esophageal ring (Schatzki's)
• Ovarian cancer
• Primary or idiopathic intestinal pseudo-obstruction

There is low radiation exposure, which carries a measurable but small risk of cancer. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most experts feel that the risk is low compared with the benefits.

Pregnant women and children are more sensitive to the risks of x-rays.

Barium may cause constipation. Consult your health care provider if the barium has not passed through your system by 2 or 3 days after the exam.

The upper GI series should be performed after other x-ray procedures, because the barium that is retained may obscure details in other imaging tests.