Late allergy-like reactions following vascular administration of radiography contrast media

Abstract

Purpose: To compare the frequency of allergy-like reactions in adults following vascular injection of iohexol and iopentol versus other contrast media (CMs), with emphasis on late reactions. Material and Methods: Thirty-two trials involving a total of 2656 patients in the European clinical development programmes for iohexol and iopentol were retrospectively evaluated. The number of patients experiencing late allergy-like reactions, immediate allergy-like reactions, and both types of reaction were pooled separately. Late was defined as time of onset being 60 min or more after the first injection of CM. Results and Conclusion: After vascular administration of iohexol and iopentol, 0.52% (0.44% and 0.68% respectively) of the patients experienced a late allergy-like reaction. The same frequency was reported for immediate allergy-like reactions. After administration of ionic CMs, the frequency of late allergy-like reactions was in the same range (0.42%) as for non-ionic CMs, but the frequency of immediate allergy-like reactions was much higher (6.99% vs 0.52%). Our results are in the same range as those reported by other authors. No serious adverse reactions were reported in the 32-trial series.