Multicenter real-world experience with epinephrine 0.5 mg dosing for anaphylaxis with allergen immunotherapy

Aim: To determine the safety and efficacy of 0.5 mg intramuscular (IM) epinephrine for the treatment of subcutaneous allergen immunotherapy induced anaphylaxis. Patients & methods: Retrospective chart review of patients who received 0.5 mg of IM epinephrine for treatment of anaphylaxis from subcutaneous allergen immunotherapy at two outpatient allergy and immunology practices. Results: Thirty-eight patients received 0.5 mg IM epinephrine. Eleven patients (29%) required a second dose, and two patients (5%) required a third dose of IM epinephrine. Sixteen patients (42%) were transferred to the emergency department with ongoing symptoms. All had eventual resolution of anaphylaxis. There were no adverse reactions or fatalities. Conclusion: IM epinephrine at a dose of 0.5 mg is safe and effective for treatment of anaphylaxis from subcutaneous allergen immunotherapy.