What It Is An upper GI (gastrointestinal) X-ray is a safe procedure that uses radiation to take a picture of the upper GI tract. It's also called an upper GI series. During the examination, a special type of X-ray camera sends beams of radiation through the upper GI tract while a child drinks a thick liquid (barium sulfate), and images are recorded on a computer. The images taken include the esophagus, stomach, and the beginning of the small intestine (called the duodenum). Barium appears white on the images, and when it fills the organs of the GI tract, it makes them visible. Gas in the stomach and intestines appears black. A radiologist uses a technique called fluoroscopy to do an upper GI series. While your child drinks, an X-ray video of the barium moving through the digestive system is watched on a screen and recorded, and a series of still X-ray films is taken. Why It's Done An upper GI X-ray is used to help find the cause of problems such as swallowing difficulties, unexplained vomiting, nausea, abdominal discomfort, and severe indigestion. It can detect signs of problems such as ulcers, gastric reflux, hiatal hernia, or blockages or narrowing of the upper GI tract. Preparation An upper GI must be done when the stomach is empty. Your child shouldn't have anything to eat or drink for a certain number of hours before the procedure — the amount of time depends on your child's age. Your child will be asked to remove clothing and jewelry and change into a hospital gown because buttons, zippers, clasps, or jewelry might interfere with the image. If your daughter is pregnant, it's important to tell the X-ray technician or her doctor. X-rays are usually avoided during pregnancy because there's a small chance the radiation may harm the developing baby. But if the X-ray is necessary, precautions can be taken to protect the fetus. It's also important to inform the technician or the doctor if your child had an X-ray exam using barium contrast material in the days prior to the upper GI series, or if your child took antidiarrheal or stomach-upset medicine containing bismuth subsalicylate, as this can interfere with the image. Also, make sure to tell the technician of any allergies your child has, as the barium sulfate may contain soy derivatives. You may want to bring a drink or snack for your child for after the procedure. Procedure The procedure can take 15-20 minutes, although actual exposure to radiation is usually only a couple of minutes or less. Your child will be asked to enter a special room that will most likely contain a table and a large X-ray machine hanging from the ceiling or wall. Parents usually are able to accompany their child to provide reassurance. If you stay in the room while the upper GI series is being done, you'll be asked to wear a lead apron to protect certain parts of your body. Your child's reproductive organs also will be protected as much as possible with a lead shield. The technician will position your child on the table and an X-ray will be taken of the stomach with nothing in it. The radiologist (a doctor who is specially trained in reading and interpreting X-ray images) will perform the test as your child drinks barium sulfate. This liquid looks like a light-colored milkshake and is often flavored for toddlers and young kids. It can be offered in a bottle or a cup with a straw. Occasionally, if the child can't drink the liquid, it can be given through a small plastic tube or syringe. The radiologist or technician may move your child on the table to help ensure that the barium coats the esophagus and stomach. As your child swallows and the barium moves through the GI tract, its path can be seen on a monitor. At some points, still images will be taken, during which older kids may be asked to hold their breath and stay still for 2-3 seconds; infants may require gentle restraint. Keeping still is important to prevent blurring of the X-ray images. What to Expect The barium sulfate that your child drinks may have a chalky taste, but it's important that the full amount requested by the doctor be taken. The positions required for the upper GI study may feel uncomfortable, but they don't need to be held for long. Babies often cry in the X-ray room, especially if they're restrained, but this won't interfere with the procedure. Barium sulfate makes stools (feces) light-colored and hard for a few days after the procedure, so giving your child extra fluids can be helpful. Getting the Results The radiologist will look at the images while the upper GI series is being done and will send a report to your doctor, who will discuss the results with you and explain what they mean. In an emergency, the results of the upper GI series can be available quickly. Otherwise, final results are usually ready in 1-2 days. Results usually can't be given directly to the patient or family at the time of the test. Risks In general, X-rays are very safe. Although there's some risk to the body with any exposure to radiation, the amount of radiation used in an upper GI is fairly small and not considered dangerous. It's important to know that radiologists use the minimum amount of radiation required to get the best results. Developing babies are more sensitive to radiation and are at more risk for harm, so if your daughter is pregnant, be sure to tell her doctor and the X-ray technician. Rarely, the barium can cause an allergic reaction. Also, there may be constipation for a few days after the procedure. A rare complication is obstruction of the GI tract. Helping Your Child You can help your child prepare for an upper GI series by explaining the test in simple terms before the procedure. It may help to explain that getting an upper GI X-ray is like being in a video. You can describe the room and the equipment that will be used and reassure your child that you'll be right there for support. Talking about the liquid that your child will need to drink can be helpful in reducing anxiety before the test. If You Have Questions If you have questions about why the upper GI is needed, speak with your doctor. You can also talk to the X-ray technician before the procedure. Back to Articles Related Articles Getting an Upper GI (Video) An upper GI is a test that shows doctors how food is moving through your digestive system. Watch how the test is done in this video for kids. Read More A to Z: Esophagitis Learn about conditions that affect the esophagus and upper gastrointestinal tract. Read More Hernias Hernias are fairly common in kids, and hernia repair is one of the most common pediatric surgeries. Read More Upper GI (Video) This video shows what it's like to get an upper GI test. Read More A to Z: Barrett's Esophagus Learn about complications of acid reflux and conditions that affect the esophagus and upper gastrointestinal tract. Read More Gastroesophageal Reflux When symptoms of heartburn or acid indigestion happen a lot, it could be gastroesophageal reflux (GER). And it can be a problem for kids - even newborns. Read More Peptic Ulcers Many people think that spicy foods cause ulcers, but the truth is that bacteria are the main culprit. Learn more about peptic ulcers. Read More Digestive System The digestive process starts even before the first bite of food. Find out more about the digestive system and how our bodies break down and absorb the food we eat. Read More Note: All information is for educational purposes only. 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