Anaphylaxis (pronounced anna-fill-axis) is a serious allergic reaction that is rapid in onset and may cause death.1

An allergen is a substance capable of causing an allergic reaction. Upon first exposure, the immune system treats the allergen as something to be rejected and not tolerated. This process is called sensitization.

Re-exposure to the same allergen in the now sensitized individual may result in an allergic reaction that, in its most severe form, is called anaphylaxis.

  1. Sampson H. et al. Second Symposium on the Definition and Management of Anaphylaxis: Summary Report – Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network Symposium.  Journal of Allergy and Clinical Immunology 2006: 117(2) 391-397.