Background Hymenoptera venom allergies in children are of concern because young patients are more prone to re-stings.

Objective This study aims to determine the protective effect of venom immunotherapy (VIT) with and without use of emergency rescue medication (ERM, i.e. oral antihistamines and steroids) to re-stings in childhood.

Methods 83 children with anaphylaxis to bee (n = 49), wasp (n = 29) or both hymenoptera venoms (n = 5) were included. Mean follow-up period was 7.7 years after commencement of VIT. We evaluated the number of re-stings, percentage of systemic reactions, number of patients carrying and taking ERM and its clinical efficacy in addition to VIT.

Results 49 children (59%) had been re-stung 108 times by the insect they were allergic to. The rate of re-stings was 0.23 per patient per year of follow-up with no difference between bee and wasp stings. 16% of children re-stung by bees developed immediate systemic reactions as compared to 6% of patients re-stung by wasps (p = 0.25). The majority of patients (87%) carried ERM, only 75% took it after re-sting. Children not taking ERM experienced significantly more frequent systemic allergic reactions to re-stings compared to those taking ERM (19% versus 4%, p<0.01). Furthermore, grades of systemic reactions were milder in children taking ERM in comparison to children not taking ERM after being re-stung.

Conclusions A majority of children are being re-stung. VIT provides complete protection in 94% with allergy to wasp venom and in 84% to bee venom. ERM provides adjunct therapy with reduced incidence and severity of systemic allergic reactions to re-stings.