Abstract
Anaphylaxis is a fatal and systemic allergic reaction, which can be prevented by avoiding exposure to a causative agent. However, the causative agent cannot be identified in all cases and may be hardly avoided. A 41-year-old man, diagnosed with idiopathic anaphylaxis, experienced 6 anaphylactic events over 7 months, requiring 4 emergency department (ER) visits and 3 epinephrine self-injections. Anti-immunoglobulin E (IgE) therapy was introduced to prevent further anaphylactic events. He experienced no anaphylactic events during 13 months of 4 monthly injections from the beginning until his most recent ER visit because of a similar anaphylactic event. We report a patient who experienced recurrent anaphylactic events that were prevented effectively by anti-IgE therapy with omalizumab. Anti-IgE therapy might be considered as an option to prevent anaphylactic events in patients for whom the causative agent(s) cannot be identified or avoided.