Like HowStuffWorks on Facebook!

Barium Swallow

What is it? A barium swallow, also known as an esophagram or upper GI series, uses a swallowed contrast solution and an X-ray to highlight the structure of your upper gastrointestinal tract, allowing the doctor to see any abnormalities or defects in your esophagus.

What is it used for? This test is used to detect strictures, or scar tissue, around the bottom of your esophagus that narrows the passageway to the stomach, which can cause dysphagia. The X-rays can also be used to detect reflux and hiatal hernia.

What can I expect? You will be asked not to eat or drink anything after midnight on the day of the exam. Prior to the exam, you swallow a thick, chalky liquid, then a thinner one. This thick drink may taste unpleasant but won't cause any side effects. In some cases, you may also eat a solid material. A series of X-rays are then taken, lasting about 30 minutes. After the exam, your stools may be chalky and light-colored for up to 72 hours. Also, you may be constipated. Your doctor can recommend a laxative to relieve any discomfort.