Health Encyclopedia:


Upper Gastrointestinal Series

What is an upper gastrointestinal series?

An upper gastrointestinal series is an imaging test of your esophagus, stomach, and first part of your small intestine (duodenum). The test is done with X-rays after you swallow a special beverage. The beverage contains either contrast or a powder called barium.

A test of just the back of your mouth and throat (pharynx) and esophagus is called a swallow. It is called a barium swallow if barium is used. It is called a Gastrografin swallow if contrast is used. Gastrografin is the brand name of diatrizoic acid, a contrast material.

X-rays use a small amount of radiation to create images of your bones and internal organs. X-rays are most often used to detect bone or joint problems, or to check the heart and lungs. An upper GI series is one type of X-ray.

Fluoroscopy is often used during an upper GI series. Fluoroscopy lets the radiologist see the barium as it moves through your upper GI tract. It is like an X-ray “movie." 

Barium absorbs X-rays and shows up white on X-ray film. When you swallow the barium, it coats the inside of your upper GI tract organs. This lets the radiologist see how you swallow. It also shows the size and shape of and how well the organs are working. These details may not be seen on standard X-rays. Barium is used only to help diagnose problems in the GI tract.

The radiologist may also use a gas during the test. You may be given a powder, tablet, or carbonated beverage that makes gas when swallowed. Or you may drink the barium through a special straw so that you swallow air with the barium. Air or gas will show up as black on X-ray film. Barium will be white. The gas also expands the organs so they can be seen better.

When the radiologist uses both barium and gas for the test, it is called a double contrast study. You may drink the water-soluble contrast instead of the barium if you have a tear or hole (perforation) in your bowel or esophagus.

Why might I need an upper gastrointestinal series?

You may need an upper GI series if your healthcare provider thinks you have a problem in your esophagus, stomach, or duodenum. These problems may include:

  • Ulcers. Ulcers may be in your stomach (gastric) or in your small intestine (enteric).
  • Gastroesophageal reflux disease (GERD)
  • Inflammation (esophagitis, gastritis, or duodenitis) or infection
  • Non-cancerous (benign) tumors
  • Cancer
  • Structural problems such as diverticula, strictures, or growths (polyps)
  • Hiatal hernia. This is when the stomach moves up, either into or alongside the esophagus.
  • Difficulty swallowing (dysphagia)
  • Food does not move as it should down your throat or esophagus
  • Chest or abdominal pain
  • Unexplained vomiting or indigestion
  • Bloody bowel movements

Your healthcare provider may have other reasons to recommend an upper GI series.

What are the risks of an upper gastrointestinal series?

You may want to ask your healthcare provider about the amount of radiation used during the test. Also ask about the risks as they apply to you.

Consider writing down all X-rays you get, including past scans and X-rays for other health reasons. Show this list to your provider. The risks of radiation exposure may be tied to the number of X-rays you have and the X-ray treatments you have over time.

Tell your provider if you are pregnant or think you may be pregnant. Radiation exposure during pregnancy may lead to birth defects.

Because contrast dye is used, there is a risk for allergic reaction to the dye. Tell your healthcare provider if you are allergic to or sensitive to any medicines, contrast dye, or iodine.

You may be constipated or have impacted stool afterward if all of the barium does not pass out of your body.

You should not have an upper GI series if you:

  • Have a hole or tear in your bowel or esophagus (perforation)
  • Have a blockage in your bowel or severe constipation
  • Are pregnant
  • Have severe difficulty swallowing. This may make it more likely for you to get barium into your lungs.

You may have other risks depending on your specific health condition. Be sure to talk with your provider about any concerns you have before the procedure.

How do I get ready for an upper gastrointestinal series?

  • Your healthcare provider will explain the procedure to you. Ask him or her any questions you have about the procedure.
  • You may be asked to sign a consent form that gives permission to do the procedure. Read the form carefully and ask questions if anything is not clear.
  • You'll be asked to not eat or drink liquids for 8 hours before the test. This usually means no food or drink after midnight. If you smoke, you should not smoke after midnight. Do not chew gum during the 8 hours before the test.
  • Tell your provider if you are allergic to or sensitive to latex, medicines, contrast dyes, or iodine.
  • Tell your provider if you are pregnant or think you may be pregnant.
  • Tell your provider about all medicines you are taking. This includes prescriptions, over-the-counter medicines, and herbal supplements. You may need to stop taking certain medicines before the test.
  • Tell the technologist if you have had a recent barium, contrast X-ray, or gallbladder scan. Any of these may make the upper GI test less accurate.
  • Follow any other instructions your provider gives you to get ready.

What happens during an upper gastrointestinal series?

You may have an upper GI series as an outpatient or as part of your stay in a hospital. The way the test is done may vary depending on your condition and your healthcare provider's practices.

Generally, an upper GI series follows this process:

  1. You'll be asked to remove any clothing, jewelry, or other objects that may get in the way of the scan.
  2. You may be asked to remove clothing. If so, you will be given a gown to wear.
  3. The technologist may take X-rays of your heart, lung, and belly (abdomen) first.
  4. The technologist will ask you to swallow some of a thick beverage. The beverage contains contrast. It is usually flavored, but it may not taste good.
  5. Or you may be given a thinner beverage if the scan uses barium.
  6. As you swallow the contrast, the technologist will take a series of X-rays or video (fluoroscopy) to watch the contrast or barium move down your throat and esophagus.
  7. You may also be asked to swallow a barium tablet. This can help the technologist see certain problems in the esophagus.
  8. The technologist may press on your abdomen during the test. This will help him or her see your stomach. It will also help the contrast coat the inside of your stomach.
  9. For a double contrast study, you may be asked to swallow a powder, tablet, or carbonated beverage. Or you may be asked to drink the barium through a special straw. The gas from the contract will expand and help the technologist see the inside of your upper GI organs. It is important not to burp.
  10. During some of the test you will be asked to stand or sit. At other times you will be placed on an X-ray table that can tilt. The table will move you from lying flat to being upright. You may be asked to change positions during the test. For example, you may need to lie on your side, back, or stomach.
  11. Once the test is done, someone will help you off the table.

What happens after an upper gastrointestinal series?

You may go back to your normal diet and activities after an upper GI series, unless your healthcare provider tells you otherwise.

You may have constipation afterward if all of the barium doesn’t pass out of your body. You may also have impacted stool because of this. You may be told to drink plenty of fluids and eat foods high in fiber to help the barium pass out of your body. You may be given a laxative to help with this.

Your bowel movements may be lighter in color until all of the barium has left your body.

You may have nausea, vomiting, or diarrhea because of the contrast material used.

Tell your health care provider if you have any of these:

  • Difficulty with bowel movements or you aren’t able to have a bowel movement
  • Pain in your abdomen or your abdomen is larger than normal (distended)
  • Stools that are smaller in size than normal

Your healthcare provider may give you other instructions, depending on your situation.

Next steps

Before you agree to the test or the procedure make sure you know:
  • The name of the test or procedure
  • The reason you are having the test or procedure
  • The risks and benefits of the test or procedure
  • When and where you are to have the test or procedure and who will do it
  • When and how will you get the results
  • How much will you have to pay for the test or procedure
Online Medical Reviewer: MMI board-certified, academically affiliated clinician
Online Medical Reviewer: Moloney Johns, Amanda, PA-C, MPAS, BBA
Last Review Date: 11/24/2013
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