Pharmaco-radiology in barium examinations with special reference to glucagon

The reasons for and objections to the use of drugs as adjuncts in barium meal and follow-through examinations are briefly reviewed. Physiological factors related to gastric emptying are considered, including the volume, temperature and osmolarity. The drugs considered include those that speed gastric emptying and small bowel transit such as metoclopramide, those that delay gastric emptying such as propantheline and gastrointestinal hormones such as glucagon. Glucagon first produces gastric and duodenal dilatation and subsequently speeds transit through the small bowel. The indications, contra-indications and side effects of these drugs are also considered and tabulated.