Fatal reactions associated with skin testing and injection immunotherapy have not been surveyed in North America since 1989.

A survey of fatal reactions related to skin testing and immunotherapy and of near-fatal immunotherapy reactions that transpired from 1990 through 2001 was conducted among member practices of the American Academy of Allergy, Asthma and Immunology.

A short survey of fatal reactions was sent to all American Academy of Allergy, Asthma and Immunology physicians, and an 87-item follow-up detailed questionnaire was sent to those reporting fatal reactions.

Of 2404 members, 646 (25%) responded to the short survey. There were 20 fatal immunotherapy reactions that were directly reported and 21 indirectly reported cases by local physicians. There were 273 (42% of the responding sample) reports of near-fatal reactions. It was estimated that fatal reactions occurred every 1 per 2.5 million injections, with an average of 3.4 deaths per year. One fatality was confirmed after skin prick testing with multiple food allergens. Of 17 fatal deaths described in long questionnaires, 15 were in asthmatic patients, the majority of whose symptoms were not optimally controlled. Three reactions occurred in a medically unsupervised setting. None were receiving β-blockers, and one was taking an angiotensin-converting enzyme inhibitor. Most fatal reactions (59%) occurred with maintenance allergen doses. The onset of 3 reactions began more than 30 minutes after injections, with a significant delay in starting epinephrine. Epinephrine was not administered in 3 other fatal reactors.

Fatal reactions to immunotherapy injections occurred at similar rates reported in previous surveys. Certain clinical practices have improved (ie, exclusion of β-blockers), and dosing errors were infrequent. Fatal reactions to immunotherapy often occur in settings inappropriate for optimal treatment of anaphylaxis. Strict adherence to practice guidelines might prevent or minimize future fatal reactions.