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Gazzetta Medica Italiana Archivio per le Scienze Mediche 2002 October;161(4-5):157-9

Copyright © 2002 EDIZIONI MINERVA MEDICA

language: Italian

X-ray contrast medium allergy

Nifosì G.

U. O. Medicina Interna, Azienda Ospedaliera Gravina, Caltagirone (Catania)

X-ray contrast media are chemical substances widely used in medicine. They may at times be responsible for severe, potentially fatal adverse reactions. At present the use of ionic or non-ionic low osmolarity preparations has greatly reduced the incidence of severe adverse reactions (0.05%). Clinically, local (rhinitis, asthma, skin reactions) and general (urticaria-angioedema, cardiopathies, anaphylactic shock, convulsions) reactions can be divided into slight, moderate and severe. Pathogenetically they act with a toxic or pseudoallergic mechanism or following complementary activation. The incidence of severe, life-threatening reactions such as severe hypotension, cardiac arrhythmias, pulmonary or laryngeal oedema and convulsions is 0.01-0.1% in patients subjected to contrastographic examinations. Patients with a previous history of anaphylactoid reactions to contrast media have a very high incidence of greater reactions and must therefore be excluded. Atopy does not significantly increase risk. Premedication with steroids and antihistaminics reduces the incidence of adverse reactions.