Injection rate: A factor in contrast reactions?

A prospective study comparing the frequency of contrast reactions by the rate of contrast injection is presented. One hundred patients undergoing excretion urography with meglumine diatriazoate (18%) and sodium diatriazoate (40%) mixture (Urografin 325) were randomised into slow (mean 0.975 ml/s) and rapid (mean 2.575 ml/s) injection groups. In the slow injection group 6 (12%) patients experienced a significant reaction as compared with 4 (8%) in the rapid injection group. There was no significant relationship between injection rate and contrast reaction ( P > 0.1).