Purpose: To compare U.S. Food and Drug Administration (FDA) and manufacturer data about patient reactions to ionic and nonionic, low- and high-osmolar contrast media from 1990 through 1994.
Materials and methods: Reactions to all available high-osmolar and four low-osmolar contrast media (ioxaglate, iohexol, iopamidol, and ioversol) were compared. Ioxaglate is composed of charged particles, and data are reported separately. Reactions were also compared with data from 1980 to 1984, when only high-osmolar contrast media were available.
Results: With high-osmolar contrast media compared with the three noncharged low-osmolar media, the incidence (per million examinations) was highest for all reported reactions (193.8 vs 44.4), severe reactions (37.4 vs 10.5), and deaths (3.9 vs 2.1). With high-osmolar media compared with ioxaglate, respectively, the incidence of total reactions was higher (193.8 vs 142.5), of severe reactions was almost the same (37.4 vs 33.6), and of death was lower (3.9 vs 6.4). The incidence of severe reactions to total reactions was higher with nonionic media (23.7%) and ioxaglate (23.6%) than with ionic media (19.3%). The incidence of death to severe reactions was 19.7% with nonionic media, 19.0% with ioxaglate, and 10.4% with high-osmolar media. The incidence of renal failure (as a percentage of total reports) was approximately 3.6 times higher with all low-osmolar contrast media (2.3%) than with high-osmolar media (0.6%), usually in patients with pathologic cardiac conditions.
Conclusion: All of these factors merit consideration in the evaluation of the utility of a given contrast medium.