A barium swallow is a medical imaging test used to examine the upper gastrointestinal tract, including the esophagus and stomach. During the procedure, a patient drinks a liquid containing barium sulfate, a contrast material that helps highlight the area on X-ray images. This allows doctors to assess swallowing function and identify any abnormalities, such as strictures or tumors. The test is typically performed in a radiology department and takes about 30 minutes. Patients may be asked to change positions during the imaging to capture different angles. After the procedure, it is important to drink plenty of fluids to help eliminate the barium from the body.