Gastrointestinal imaging is usually not very painful. Gastrointestinal imaging can be categorized as upper GI, lower GI, and total GI. Upper GI and total GI imaging are generally painless, while lower GI imaging can produce nausea, bloating, and other uncomfortable symptoms. During upper GI and total GI imaging, contrast agents such as barium sulfate are administered orally to make a diagnosis of GI disorders through the distribution of the contrast agent in the upper GI tract (esophagus, stomach, duodenum) and small intestine. The procedure is non-invasive and painless, and the patient only needs to take the contrast agent orally and assume the required position under the direction of the doctor. Lower gastrointestinal imaging, mainly referred to as barium enema examination, injects barium directly into the rectum and colon through the anus, thus visualizing the rectum and colon. This process may cause discomfort to the patient, producing bloating, abdominal pain, diarrhea, and nausea.