Upper gastrointestinal series (or study), whereas the barium enema is called a lower gastrointestinal series (or study). In upper gastrointestinal series examinations, the barium sulfate is mixed with water and swallowed orally, whereas in the lower gastrointestinal series (barium enema), the barium contrast agent is administered as an enema through a small tube inserted into the rectum. Barium X-ray examinations are useful tools for the study of appearance and function of the parts of the gastrointestinal tract. They are used to diagnose and monitor esophageal reflux, dysphagia, hiatus hernia, strictures, diverticula, pyloric stenosis, gastritis, enteritis, volvulus, varices, ulcers, tumors, and gastrointestinal dysmotility, as
Colon cleansing support, "auto-intoxication" persists in the public imagination. The practice of colon cleansing has undergone a resurgence in the alternative-medical community, supported by testimonials and anecdotal evidence and promoted by manufacturers of colon-cleansing products. In the United States the Food and Drug Administration (FDA) regulates the production of equipment used in colon hydrotherapy in the USA but does not regulate their use, or the supplements used in oral colon-cleansing regimens and manufacturer claims do not require verification or supporting evidence. The contents of the products are also not verified or tested. The FDA has issued several letters warning manufacturers and suppliers