“…These are divided into mild (nausea, vomiting, pruritus, sneezing, vaso-vagal disorders, inadvertent arterial injection), moderate (urticaria, other skin eruptions, syncope, thrombophlebitis, pyrexia, local tissue necrosis, muscular paralysis) and severe (bronchospasm, laryngeal edema, circulatory shock, myocardial infarction, tonic-clonic seizure) (5)(6)(7) . Previous studies indicate that the most frequent adverse reactions are mild, such as nauseas and vomiting (2% to 14%) and that moderate and severe reactions are infrequent (<1%) (5)(6)8) . The reported frequency of these adverse reactions has varied among authors, however most of the studies are retrospective and they do not distinguish patients who had previously undergone this test from those who had undergone it for the first time (7,(9)(10) .…”