Risk factors for systemic reactions to allergen immunotherapy

Purpose of review To update safety information regarding allergen-specific immunotherapy (ASIT) in clinical practice and highlight the risk factors associated with the adverse reactions, product and each dose. Recent findings Efforts in recent years have focused on increasing our understanding of the efficacy and safety of ASIT, especially the sublingual variety (SLIT), in multicenter studies. Moreover, new Clinical Practice Guidelines (CPGs) and an international consensus concerning ASIT have been published recently. Although no deaths as a result of subcutaneous immunotherapy or SLIT have been reported in the last 2 years, systemic reactions mainly arising from administration errors still appear. Recent studies support the safety of new forms of specific immunotherapy. Summary An understanding of the risk factors for each patient, product and dose, and the implementation of CPGs are the main factors that could improve the safety of ASIT. The standardization of all procedures for prescribing and administering ASIT, and the systematic collection of standardized safety data in a multicenter database (postmarketing surveillance), may be required to generate new information on the safety of ASIT.