Recognition and first-line treatment of anaphylaxis.

The International Classification of Diseases (ICD)-9 included a code only for anaphylactic shock. The improved ICD-10 coding defines the different symptoms and types of anaphylaxis and includes coding for anaphylaxis without shock. This new coding is consistent with the efforts of the National Institute of Allergy and Infectious Diseases (NIAID) and the Food Allergy and Anaphylaxis Network (FAAN), who convened a panel to formulate a definition of and the diagnostic criteria for anaphylaxis. Anaphylaxis is a serious reaction that has a rapid onset and may cause death. It is a systemic immunoglobulin E-mediated reaction resulting from the sudden release of multiple mediators from mast cells and basophils. Foods are the most common triggers for anaphylactic reactions, followed by drugs, insect stings, and idiopathic anaphylaxis (anaphylaxis of unknown cause). If the NIAID/FAAN criteria are met and anaphylaxis is diagnosed, epinephrine administration is mandatory. Delays in epinephrine administration have been associated with fatalities. Patients should have ready access to >1 epinephrine autoinjector in the outpatient setting. An individualized emergency action plan should be developed for each patient at risk for anaphylaxis.