Upper Gastrointestinal (UGI) Series
An upper gastrointestinal (UGI) series looks at the upper and middle sections of the gastrointestinal tract. The test uses barium contrast material, fluoroscopy, and X-ray. Before the test, you drink a mix of barium (barium contrast material) and water. The barium is often combined with gas-making crystals. Your doctor watches the movement of the barium through your esophagus, stomach, and the first part of the small intestine (duodenum) on a video screen. Several X-ray pictures are taken at different times and from different views.
A small bowel follow-through may be done immediately after a UGI to look at the rest of the small intestine. If just the throat and esophagus are looked at, it is called an esophagram (or barium swallow).
Upper endoscopy is done instead of a UGI in certain cases. Endoscopy uses a thin, flexible tube (endoscope) to look at the lining of the esophagus, stomach, and upper small intestine (duodenum).
Why It Is Done
An upper gastrointestinal (UGI) series is done to:
- Find the cause of gastrointestinal symptoms, such as trouble swallowing, vomiting, burping up food, belly pain (including a burning or gnawing pain in the center of the stomach), or indigestion.
- Find narrow spots (strictures) in the upper intestinal tract, ulcers, tumors, polyps, or pyloric stenosis.
- Find inflamed areas of the intestine, malabsorption syndrome, or problems with the squeezing motion that moves food through the intestines (motility disorders).
- Find swallowed objects.
Generally, a UGI series is not used if you do not have symptoms of a gastrointestinal problem. A UGI series is done most often for people who have:
- A hard time swallowing.
- A possible blocked intestine (obstruction).
- Belly pain that is relieved or gets worse while eating.
- Severe heartburn or heartburn that occurs often.
How To Prepare
Tell your doctor if you:
- Are taking any medicine.
- Are allergic to any medicines, barium, or any other X-ray contrast material.
- Are or might be pregnant. This test is not done during pregnancy because of the risk of radiation to the developing baby (fetus).
You may be asked to eat a low-fiber diet for 2 or 3 days before the test. You may also be asked to stop eating for 12 hours before the test. Your doctor will tell you if you need to stop taking certain medicines before the test.
The evening before the test, you may be asked to take a laxative to help clean out your intestines. If your stomach can't empty well on its own, you may have a special tube put through your nose and down into your stomach just before the test begins. A gentle suction on the tube will drain the stomach contents.
If you are having the small bowel follow-through after the UGI series, you will need to wait between X-rays. The entire small bowel follow-through exam takes up to 6 hours, so bring along a book to read or some other quiet activity.
You may be asked to sign a consent form.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form ( What is a PDF document? ).
How It Is Done
A UGI series is usually done in a clinic or the X-ray department of a hospital. You do not need to stay overnight in the hospital. The test is done by a radiologist and a radiology technologist.
Before the test
You will need to take off your clothes and put on a hospital gown. You will need to take out any dentures and take off any jewelry. You may not smoke or chew gum during the test, since the stomach will respond by making more gastric juices and this will slow the movement of the barium through the intestines.
You will lie on your back on an X-ray table. The table is tilted to bring you to an upright position with the X-ray machine in front of you. Straps may be used to keep you safely on the table. The technologist will make sure you are comfortable during changes in table position.
During the test
You will have one X-ray taken before you drink the barium mix. Then you will take small swallows repeatedly during the series of X-rays that follow. The radiologist will tell you when and how much to drink. By the end of the test, you may have swallowed 1 cup (240 mL) to 2.5 cup (600 mL) of the barium mixture.
The radiologist watches the barium pass through your gastrointestinal tract using fluoroscopy and X-ray pictures. The table is tilted at different positions and you may change positions to help spread the barium. Some gentle pressure is put on your belly with a belt or by the technologist's gloved hand. You may be asked to cough so that the radiologist can see how that changes the barium flow.
If you are having an air-contrast study, you will sip the barium liquid through a straw with a hole in it or take pills that make gas in your stomach. The air or gas that you take in helps show the lining of the stomach and intestines in greater detail.
If you are also having a small bowel study, the radiologist watches as the barium passes through your small intestine into your large intestine. X-ray pictures are taken every 30 minutes.
The UGI series takes 30 to 40 minutes. The UGI series with a small bowel study takes 2 to 6 hours. In some cases, you may be asked to return after 24 hours to have more X-ray pictures taken.
After the test
When the UGI series is done, you may eat and drink whatever you like, unless your doctor tells you not to.
You may be given a laxative or enema to flush the barium out of your intestines after the test to prevent constipation. Drink a lot of fluids for a few days to flush out the barium.
How It Feels
The barium liquid is thick and chalky, and some people find it hard to swallow. A sweet flavor, like chocolate or strawberry, is used to make it easier to drink. Some people do not like it when the X-ray table tilts. You may find that pressure on your belly is uncomfortable. After the test, many people feel bloated and a little nauseated.
For 1 to 3 days after the test, your stool (feces) will look white from the barium. Call your doctor if you are not able to have a bowel movement in 2 to 3 days after the test. If the barium stays in your intestine, it can harden and cause a blockage. If you become constipated, you may need to use a laxative to pass a stool.
Barium does not move into the blood, so allergic reactions are very rare.
Some people gag while drinking the barium fluid. In rare cases, a person may choke and inhale (aspirate) some of the liquid into the lungs.
There is a small chance that the barium will block the intestine or leak into the belly through a perforated ulcer. A special type of contrast material (Gastrografin) can be used if you have a blockage or an ulcer.
There is always a small chance of damage to cells or tissue from being exposed to any radiation, even the low level of radiation used for this test.
An upper gastrointestinal (UGI) series looks at the upper and middle sections of the gastrointestinal tract. Results are usually ready in 1 to 3 days.
The esophagus, stomach, and small intestine all look normal.
A narrowing (stricture), inflammation, a mass, a hiatal hernia, or enlarged veins (varices) may be seen. Spasms of the esophagus or a backward flow (reflux) of barium from the stomach may occur.
The UGI series may show a stomach (gastric) or intestinal (duodenal) ulcer, a tumor, or something pushing on the intestines from outside the gastrointestinal tract. Narrowing of the opening between the stomach and the small intestine (pyloric stenosis) may be seen.
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
- Eating before or during the test.
- Too much air in the small intestine.
What To Think About
- A gastrointestinal (GI) motility study may be done if the squeezing motions of the small intestine are not normal during the UGI series and small bowel follow-through. The movement of the barium through the lower intestinal tract is recorded every few hours for up to 24 hours. A barium enema or colonoscopy may be needed to confirm the diagnosis.
- Upper endoscopy is done instead of a UGI test in certain cases. Endoscopy uses a thin, flexible tube (endoscope) to look at the lining of the esophagus, stomach, and upper small intestine (duodenum). To learn more, see the medical test Upper Gastrointestinal Endoscopy.
- The UGI series test:
- May not show irritation of the stomach lining (gastritis) or esophagus (esophagitis) or ulcers that are smaller than about 0.25 in. (6 mm) in diameter.
- Cannot show an infection with the bacteria Helicobacter pylori, which may be a cause of stomach ulcers.
- A biopsy cannot be done during the UGI if a problem is found.
Other Works Consulted
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Current as of: March 28, 2019
Author: Healthwise Staff
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Jerome B. Simon MD, FRCPC, FACP - Gastroenterology