Allergic patients frequently suffer from infections. Allergen immunotherapy (AIT) usually improves respiratory symptoms, mainly in allergic rhinitis (AR). This study was aimed at evaluating the possible impact of AIT on extra-allergic outcomes in a cohort of Italian children with respiratory allergy patients. The study was performed on 77 children (43 males, mean age 10.5 years) with AR. The kind and the number of prescribed allergen extracts, type of diagnosis, severity of symptoms, and use of drugs were evaluated at baseline and after 2 year AIT. Globally 40 patients were treated with AIT, the remaining 37 children served as control. AIT-treated children had lower symptoms, drug use, and less severe extra-allergic surrogate markers of infection in comparison with children untreated with AIT. In conclusion, this study provides the first evidence that 2-year SLIT is able of exerting an adjunctive anti-allergic activity in AR children.