Late and acute adverse reactions to iohexol in a pediatric population.

The purpose of this study was to determine the incidence of acute and late reactions after contrast-medium injection in the Finnish paediatric population. From March 1989 to November 1990, 321 children under 19 years of age were examined with a nonionic contrast medium, iohexol, for urography and CT. The follow-up time for late reactions was up to 24 h after the contrast-medium injection. The return rate for the questionnaires given to patients to record their reactions was 73.2%. Acute adverse reaction was noted in 1.9% of the patients, with the most frequent reactions being in the weight range 24-40 kg. Asthma and previous reaction to contrast medium are risk factors for acute reaction. Late reactions were found in 6.2% of the patients, most frequently in children weighing under 24 kg.