Adverse reactions to intravenous contrast agents in Ontario, 1975 - 1979.

A retrospective study of severe adverse reactions to intravenous contrast agents used for intravenous pyelography and enhanced CT scans is reported. There was no difference between large and small hospitals in the incidence and management of serious reactions to these agents. In spite of 81 cardiac or respiratory arrests during over 450,000 intravenous urograms in Ontario, only five deaths occurred.