“… 3 In Brazil, a cross-sectional study carried out by answering a questionnaire (although without further investigation) indicated the incidence of anaphylaxis as greater than 7:10,000 anesthesias, which is higher than the previously described figure in the literature. 4 The greatest risk factor for perioperative hypersensitivity reaction is an earlier reaction, without adequate investigation. 5 , 6 The collaboration among anesthesiologists, allergists and immunologists is fundamental to carry out the investigation.…”