The current status of reactions to intravenous contrast media.

A prospective 12-month survey in 272 United Kingdom hospitals was performed and data are presented on the incidence of adverse reactions following intravenous urography, contrast CT scanning, and intravenous cholangiography. Minor and intermediate reactions are commonest in young adults, but severe and fatal reactions predominate in the older age group. There is an increased risk of severe reactions in patients with a history of allergy or previous reaction to contrast media and in patients with heart disease. The risk of severe reaction is also increased in certain ethnic groups. There appears to be an association between the incidence of severe reactions and contrast medium dose. Etiology, prevention and treatment of reactions are briefly discussed.