Adverse reactions during intravenous urography: are these due to histamine release?

The effects of four different radiographic contrast media (Urovison 58%, Hexabrix 320, Iopamiro 370 and Omnipaque 300) have been examined with respect to histamine release, cardiovascular changes and adverse drug reaction (ADR) in a group of 200 patients undergoing intravenous urography. Each patient received only one of the four agents, which were allocated on a random basis. Urovison produced the greatest number of ADRs. Iopamiro caused the least. No significant correlation between the magnitude of the change in plasma histamine following injection of radiographic contrast medium and the production of a particular ADR could be demonstrated. Heart rate increased significantly following the administration of Urovison, Hexabrix and Iopamiro in the absence of any appreciable change in blood pressure. These results and our earlier findings would favour the use of the low-osmolality contrast media in intravenous urography to minimize ADRs, histamine release and patient discomfort.