Factors Affecting the Safety and Effectiveness of Venom Immunotherapy

Abstract

Background: The safety profile of venom immunotherapy (VIT) is a relevant issue, and considerable differences have been reported in the safety and efficacy of this treatment modality. The primary aim of this study was to evaluate the safety of angiotensin-converting enzyme inhibitors and ß-blockers during VIT. In a second analysis, we evaluated data on premedication and venom preparations and their association with systemic adverse events (AEs) during the up-dosing phase and the first year of the maintenance phase, as well as the outcome of field stings and sting challenges. Methods: Ours was an open, prospective, observational, multicenter study that recruited 1425 patients, of whom 1342 underwent VIT. Results: Premedication with oral antihistamines was taken by 52.1% of patients during up-dosing and 19.7% of patients during the maintenance phase. Antihistamines had no effect on the frequency of systemic AEs (P=.11), although large local reactions (LLRs) were less frequent (OR, 0.74; 95%CI, 0.58-0.96; P=.02). Aqueous preparations were preferred for up-dosing (73.0%), and depot preparations were used for the maintenance phase (64.5%). The type of venom preparation had no influence on the frequency of systemic AEs or on the effectiveness of VIT (P=.26 and P=.80, respectively), while LLRs were less frequent with depot preparations (P