Reduction of side-effects from ultrarush immunotherapy with honeybee venomby pretreatment with fexofenadine: a double-blind, placebo-controlled trial

Background: Immunotherapy with Hymenoptera venoms is highly effective but c auses allergic side-effects frequently, especially when honeybee venom is u sed. Therefore, our objective was to investigate the effect of pretreatment with the antihistamine fexofenadine on the incidence of allergic side-effe cts during ultrarush immunotherapy with bee venom. Methods: In a double-blind, placebo-controlled trial, 57 patients with a hi story of systemic allergic reactions to honeybee stings and positive diagno stic tests (skin tests, serum specific IgE to honeybee venom) were investig ated. Bee venom immunotherapy was started with an ultrarush protocol and pa tients were randomized to pretreatment with either fexofenadine 180 mg or p lacebo on days 1, 8, 22, and 50 of the protocol. Local and systemic allergi c side-effects were registered. Results: Fifty-four patients completed the study, 28 on fexofenadine and 26 on placebo pretreatment. On day 1, large local reactions were significantl y reduced in both er;tension and duration by fexofenadine pretreatment (P < 0.025). Systemic allergic side-effects on the whole were not reduced. Howe ver, the symptoms pruritus, urticaria, and angioedema occurred less frequen tly with fexofenadine (P < 0.05). Conclusions: Pretreatment with fexofenadine during venom immunotherapy redu ces local allergic reactions and generalized symptoms of the urticaria and angioedema type.