Background: Although rapid venom immunotherapy (VIT) protocols have been shown to be safe and effective, this issue has not yet been clarified in Turkey.

Objective: The aim of this study was to evaluate the side effects of rush VIT as well as early clinical and immunological responses in patients with a venom allergy.

Methods: Eighteen patients who had a history of severe systemic reactions after Hymenoptera sting were included in the study. The diagnosis was made on the basis of positive skin test reactivity and the presence of specific IgE in serum to either bee or vespid venoms. Fourteen patients underwent an average 7-day rush VIT regimen under
careful monitoring in our clinic. Among them 7 patients were treated with Vespula species and 7 with Apis mellifera venom extracts. Four patients were followed up as a control group. Skin test response, specific IgE and IgG4 levels were determined before and after a year of VIT. Local and systemic reactions due to injections were monitored
during the induction and maintenance phases of VIT.

Results: Specific IgG4 levels significantly increased after 1 year compared with levels before VIT (mean concentration before and after; 13.04 vs 21.85 mg/L, respectively; P <. 05) whereas specific IgE levels did not change (11.54 vs 13.32 kU/L). No significant differences were observed before and after one year of VIT in skin prick (2.34 vs 3.66 mm) and intradermal (0.12-0.11 µg/mL) test reactivities (P > .05). A single patient treated with bee venom developed 4 mild systemic reactions (4/469 injections, 0.85%) during the course of VIT. More local reactions occurred in patients receiving bee venom extract (3.33 %) than in those receiving yellow jacket venom (1.33%). Two patients tolerated field stings without reactions.

Conclusion: Our experience confirms that rush VIT is safe and has a low systemic reaction. It can be considered for patients requiring rapid protection.

Key words: Venom immunotherapy. Efficacy. Safety.