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Upper Gastrointestinal (GI) Series

What is an upper gastrointestinal series?

An upper gastrointestinal (GI) series is an imaging test. It takes images of your esophagus, stomach, and the first part of your small intestine (duodenum). The test is done with X-rays after you swallow a special drink that contains a barium contrast. This makes it easier to see the images on the X-rays.

A test of just the back of your mouth and throat (pharynx) and esophagus is called a swallow. It's called a barium swallow if barium is used. It's called a Gastrografin swallow if a different type of contrast dye (diatrizoic acid) is used. This contrast dye dissolves in water (water-soluble).

Fluoroscopy is also used during an upper GI series. Fluoroscopy lets the radiologist see the barium as it moves through your upper GI tract. It's 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 your organs and how well they 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 drink 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's 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 in your stomach (gastric) or small intestine (enteric)

  • GERD (gastroesophageal reflux disease)

  • Inflammation (esophagitis, gastritis, or duodenitis) or infection

  • Noncancer (benign) tumors

  • Cancer

  • Structural problems such as diverticula, strictures, or growths (polyps)

  • Hiatal hernia (when the stomach moves up, either into or alongside the esophagus)

  • Trouble swallowing (dysphagia)

  • Food doesn't move as it should down your throat or esophagus

  • Anatomy problems such as twisting of the intestines (malrotation)

  • Chest or belly pain

  • Unexplained vomiting or indigestion

  • Unexplained weight loss

  • Bloody bowel movements

Your healthcare provider may have other reasons to advise 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 very common 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 doesn't pass out of your body.

You should not have an upper GI series with barium if you:

  • Have a hole or tear in your bowel or esophagus (perforation). Water soluble contrast can be used in these cases.

  • Have a blockage in your bowel or severe constipation

  • Are pregnant

  • Have severe trouble swallowing. This may make it more likely for you to get barium into your lungs.

You may have other risks depending on your health. Be sure to talk with your healthcare 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 them any questions you have about the procedure.

  • You will be asked to sign a consent form that gives permission to do the procedure. Read the form carefully and ask questions if anything isn't clear.

  • Follow any directions you are given for not eating or drinking before the test. This often means no food or drink after midnight. If you smoke, you shouldn't smoke after midnight. Don't 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, vitamins, 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 healthcare provider gives you to get ready.

What happens during an upper gastrointestinal series?

You may have an upper GI series as an outpatient. This means you go home the same day. Or it may be done as part of a hospital stay. 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 will be asked to remove clothing and you will be given a gown to wear.

  3. The technologist may take X-rays of your heart, lung, and belly first.

  4. The technologist will ask you to swallow some of a thick drink. The drink contains contrast. It's often flavored, but it may not taste good.

  5. You may be given a thin and thicker version of the barium.

  6. As you swallow the contrast, the radiologist 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 radiologist see certain problems in the esophagus.

  8. The radiologist may press on your belly (abdomen) during the test. This will help them 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 drink. 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's 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 will be asked to change positions during the test. For instance, 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 healthcare provider if you have any of these:

  • Trouble with bowel movements or you aren’t able to have a bowel movement

  • Pain in your belly or your belly is larger than normal (distended)

  • Stools that are smaller in size than normal

Your healthcare provider may give you other instructions.

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

  • What results to expect and what they mean

  • The risks and benefits of the test or procedure

  • What the possible side effects or complications are

  • When and where you are to have the test or procedure

  • Who will do the test or procedure and what that person’s qualifications are

  • What would happen if you did not have the test or procedure

  • Any alternative tests or procedures to think about

  • When and how you will get the results

  • Who to call after the test or procedure if you have questions or problems

  • How much you will have to pay for the test or procedure

Online Medical Reviewer: Marianne Fraser MSN RN
Online Medical Reviewer: Raymond Turley Jr PA-C
Online Medical Reviewer: Shaziya Allarakha MD
Date Last Reviewed: 2/1/2024
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.