In upper GI small bowel series, you ingest a liquid mixture containing barium sulfate, a contrast dye that delineates your upper gastrointestinal (GI) tract on x-rays and reveals any abnormalities. Examination of the esophagus, the stomach, and the upper part of the small intestine (duodenum) is known as an upper GI series. In some cases, the flow of barium is followed through the entire 20-foot length of the small intestine; this is called a small bowel series. This test is often performed in conjunction with a barium swallow and enteroclysis.

Purpose of the Upper GI and Small Bowel Series

  • To examine the upper GI tract in people with symptoms such as difficulty swallowing, regurgitation, burning or gnawing stomach pain, diarrhea, weight loss, vomiting of blood, and black, tarry stool
  • To detect abnormalities of the upper GI tract, such as strictures (narrowings), ulcers, tumors, inflammatory conditions, esophageal diverticula (abnormal pouches), and hiatal hernia (a condition in which a portion of the stomach protrudes upward through the diaphragm)

Who Performs Upper GI and Small Bowel Series

  • A radiologist

Special Concerns about Upper GI and Small Bowel Series

  • Patients with an intestinal obstruction should not undergo this procedure.
  • When perforation of the upper GI tract is suspected, barium is not used because leakage of the dye could worsen any existing infection. A water-soluble contrast agent, diatrizoate (Gastrografin), is usually substituted.
  • Pregnant women should not undergo this test because exposure to ionizing radiation may harm the fetus.
  • Patients with a poor swallowing reflex may inadvertently aspirate barium into their lungs. Your swallowing reflex may be assessed before the test.
  • Patients with unstable vital signs must be closely monitored during this test.

Before the Upper GI and Small Bowel Series

  • Be sure to inform your doctor of all medications you are taking. You may need to discontinue certain medications for up to 24 hours before the test. Ask your doctor about any dietary or medication restrictions before the test.
  • Tell your doctor if you are pregnant or may be pregnant.
  • Do not smoke for a period time before the test, as instructed by your doctor, or eat after midnight on the day of the test.
  • Remove any metallic objects, such as jewelry, watches, dentures, or hairpins before the test begins.

What You Experience during Upper GI and Small Bowel Series

  • You are asked to drink a thick, milkshake-like liquid containing the barium sulfate. The barium has a chalky taste, but is usually flavored to increase its palatability.
  • In a radiology room, you are strapped securely to a tilting x-ray table.
  • The x-ray table is tilted into various positions to ensure that the dye sufficiently coats the GI tract. Your abdomen may also be palpated to ensure your stomach is adequately coated.
  • The radiologist observes the flow of the barium through your esophagus, stomach, and, if necessary, duodenum via fluoroscopy, which transmits continuous, moving x-ray images onto a viewing screen.
  • Spot x-ray films are taken of any significant abnormalities. As each x-ray is taken, you will be instructed to hold your breath and remain very still.
  • In some cases, you may be asked to swallow a carbonated powder, which creates carbon dioxide in your stomach and enhances visualization of the stomach lining, during the test.
  • The test is painless, but you may occasionally experience a feeling of bloating or nausea.
  • The procedure takes about 30 to 60 minutes.

Risks and Complications of Upper GI and Small Bowel Series

  • Although radiation exposure is minimal, you receive a higher dose of radiation than during standard x-ray procedures.
  • The x-ray may cause mild bloating but usually causes no discomfort.
  • Pregnant women usually should not undergo this test because of risks to the fetus.
  • Children are more sensitive to the risks of x-rays.
  • The barium may accumulate and block the intestines if it is not excreted within a few days.

After the Upper GI and Small Bowel Series

  • Drink plenty of fluids to help eliminate the barium. Your doctor may also give you a mild laxative to purge your body of the contrast agent.
  • Your stool will be chalky and light-colored initially, but should return to normal color after 1 to 3 days.
  • Inform your doctor if you experience abdominal fullness or pain after the procedure.
  • If diatrizoate was used rather than barium, you may experience transient diarrhea.
  • You may resume your normal diet, medications and activities.

Results of Upper GI and Small Bowel Series

  • The doctor will examine the recorded x-ray images for signs of any abnormality, including strictures, tumors or ulcers.
  • If a definitive diagnosis can be made, appropriate treatment will be initiated.
  • In some cases, additional tests, such as a biopsy or endoscopic retrograde cholangiopancreatography, may be needed to further evaluate abnormal results.


The Johns Hopkins Consumer Guide to Medical Tests

Simeon Margolis, M.D., Ph.D., Medical Editor

Updated by Remedy Health Media

Publication Review By: the Editorial Staff at

Published: 24 Jan 2012

Last Modified: 11 Sep 2015