An upper GI and small bowel series is done in a doctor's office or hospital radiology department.
You may be given an injection of a medicine that slows muscle movement in the small intestine. This lets the doctor see structures can be more easily on the x-rays.
Before the x-rays are taken, you must drink 16 - 20 ounces of a milkshake-like drink. The drink contains a substance called barium, which shows up well on x-rays.
An x-ray method called fluoroscopy tracks how the barium moves through your esophagus, stomach, and small intestine. Pictures are taken with you in a variety of positions. You may be sitting or standing.
The test usually takes around 3 hours but can take as long as 6 hours to complete.
A GI series may include this test or a barium enema.
How to prepare for the test
You may have to change your diet for 2 or 3 days before the test. Usually, you cannot eat for a period of time before the test.
Be sure to ask your health care provider if you need to change how you take any of your medicines. Often, you can continue taking the medicines you take by mouth. Never make any changes in your medicines without first talking to your health care provider.
You will be asked to remove all jewelry on your neck, chest, or abdomen before the test.
How the test will feel
The x-ray may cause mild bloating but usually causes no discomfort. The barium milkshake feels chalky as you drink it.
Why the test is performed
This test is done to look for a problem in the structure or function of your esophagus, stomach, or small intestine.
A normal result shows that the esophagus, stomach, and small intestine are normal in size, shape, and movement.
Normal value ranges may vary depending on the lab doing the test. Talk to your doctor about the meaning of your specific test results.
There is low radiation exposure, which carries a very 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 should usually not have this test. 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 done after other x-ray procedures, because the barium that remains in the body may block details in other imaging tests.
Caroline DF, Kendzierski RM. The stomach. In: Adam A, Dixon AK, eds. Grainger & Allison's Diagnostic Radiology. 5th ed. Philadelphia, Pa: Churchill Livingstone Elsevier; 2008:chap 31.
George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, and Stephanie Slon.