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Upper GI Exam

Upper gastrointestinal tract radiography, also called an upper GI exam, is an x-ray examination of the pharynx, esophagus, stomach and first part of the small intestine (also known as the duodenum) that uses a special form of x-ray called fluoroscopy and an orally ingested contrast material called barium. 

An x-ray (radiograph) is a non-invasive medical test that helps physicians diagnose and treat medical conditions.

An upper GI examination helps evaluate digestive function and to detect:

  • ulcers
  • tumors, inflammation of the esophagus, stomach and duodenum
  • hiatal hernias
  • scarring
  • blockages
  • abnormalities of the muscular wall of GI tissues

The procedure is also used to help diagnose symptoms such as:

  • difficulty swallowing
  • chest and abdominal pain
  • reflux (a backward flow of partially digested food and digestive juices)
  • unexplained vomiting
  • severe indigestion
  • blood in the stool (indicating internal GI bleeding)

Contact Information

To book or follow up on the status of your appointment, please contact:

Mississauga Hospital or Queensway Health Centre:
Phone: 416-521-4069
Fax: 416-521-4014

Credit Valley Hospital:
Phone: 905-813-2731
Fax: 905-813-4418

Resources for Patients & Their Families

How to Prepare for Your Procedure

Let your doctor know about any medications you are taking and if you have any allergies, especially to barium or iodinated contrast materials. Also let your doctor know about recent illnesses or other medical conditions.

Women should always let their doctor or x-ray technologist know if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to radiation. If an x-ray is necessary, precautions will be taken to minimize radiation exposure to the baby. To ensure the best possible image quality, your stomach must be empty of food. Therefore, you must not to eat or drink anything (including any medications taken by mouth, especially antacids) and to refrain from chewing gum and smoking after midnight on the day of the examination.

You may be asked to remove some or all of your clothes and to wear a gown during the exam. You may also be asked to remove jewelry, eye glasses and any metal objects or clothing that might interfere with the x-ray images.

What to Expect from Your Procedure

This examination is usually performed on an outpatient basis and is often scheduled in the morning to reduce the amount of time you must fast.

A radiological technologist and a radiologist, a physician specifically trained to supervise and interpret radiology examinations, guide the patient through the upper GI series.

As you drink the liquid barium, which resembles a light-colored milkshake, the radiologist will watch the barium pass through the patient's digestive tract on a fluoroscope, a device that projects radiographic images in a movie-like sequence onto a monitor. The exam table will be positioned at different angles and the patient's abdomen may be compressed to help spread the barium. Once the upper GI tract is adequately coated with the barium, still x-ray images will be taken and stored for further review.

You will be asked to hold very still and may be asked to keep from breathing for a few seconds while the x-ray picture is taken to reduce the possibility of a blurred image.

For a double-contrast upper GI series, you will swallow baking-soda crystals that create gas in the stomach while additional x-rays are taken

When the examination is complete, you will be asked to wait until the radiologist determines that all the necessary images have been obtained.
This exam is usually completed within 20 minutes.

How It Works

Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.

Fluoroscopy makes it possible to see internal organs in motion. When the upper GI tract is coated with barium, the radiologist is able to view and assess the anatomy and function of the esophagus, stomach and duodenum.

An x-ray examination that evaluates only the pharynx and esophagus is called a barium swallow.

In addition to drinking barium, some patients are also given baking-soda crystals (similar to Alka-Seltzer) to further improve the images. This procedure is called an air-contrast or double-contrast upper GI.