An upper gastrointestinal (UGI) series is a multi-step test a doctor uses to examine the upper portion of a person's gastrointestinal tract.
The person being tested swallows a chalky-tasting "milk shake" of barium and water (barium contrast material) followed by gas-producing crystals. The doctor then tracks the progress of the barium through the throat (esophagus), stomach, and the first part of the small intestine (duodenum) using a device called a fluoroscope that takes pictures. The fluoroscope is connected to a TV monitor. Several X-ray pictures are usually taken at different times and from different angles.
An upper GI series may be done to:
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