Venom Immunotherapy: a 20-year experience with an ultra-rush protocol (210-min).

SUMMARY: Background. Ultra-rush (UR) are induction protocols used in venom immunotherapy (VIT). Objectives: To evaluate the adverse reactions during a 210-minutes UR and determine possible risk factors. Methods: Retrospective study of 129 patients submitted to UR with VIT in the last 20 years. Results: In 114 (88.4%) patients the 101.1 µg maintenance dose was reached in 210 minutes. Systemic reactions (SR) occurred in 22% of patients (71% mild). There were no severe SR, late reactions or fatalities. Adrenaline was administered in 10% of all UR. The SR were more frequent with honey bee VIT and had greater severity in the patients with a previous severe systemic sting reaction. No significant difference in the risk of SR was found with other demographic, clinical or laboratory factors. There were 5% of large local reactions (LLR), these being more frequent in females. Conclusion: Most SR during UR were mild with no need for adrenaline treatment. The honey bee venom and the severity of the anaphylaxis during the field sting were the only SR´s risk factors for systemic adverse reactions during the UR.