ALTHOUGH iodopyracet (diodrast®) is the most commonly employed contrast material for intravenous urography, it has many undesirable reactions. The majority of these are not serious and are of brief duration, such as flushing, nausea, sneezing, and urticaria. Occosionally, however, one encounters reactions of a graver nature, and with the extensive use of this contrast material over many years several anaphylactoid deaths directly attributable to its intravenous injection have been recorded in the literature.1
Many authors believe that a fair proportion of the side-reactions have an allergic basis. In the light of present trends to incriminate histamine as the means by which allergic phenomena are mediated, a study was undertaken to determine the effect of administering an antihistaminic just prior to the injection of iodopyracet.
PROCEDURES AND RESULTS
The first series comprises 200 patients who were referred for intravenous urography. A detailed personal and family history with regard to