Anaphylaxis is a rarely anticipated, potentially life-threatening systemic allergic reaction with symptoms ranging from mild flushing to upper respiratory obstruction with or without vascular collapse. Early recognition of symptoms with prompt institution of therapy is central to a successful outcome. Anaphylaxis is IgE mediated, whereas non-IgE mediated anaphylatic reactions are termed anaphylactoid. Food-induced anaphylactic reactions, particularly peanut, are being recognized with increasing frequency. Central to appropriate therapy of the acute reaction is adminstration of intramuscular adrenalin. However, with the advent of humanized anti-IgE monoclonal antibody, such reactions may be reduced in frequency and severity.