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

To determine the safety and efficacy of 0.5 mg intramuscular (IM) epinephrine for the treatment of subcutaneous allergen immunotherapy induced anaphylaxis. 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. 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. IM epinephrine at a dose of 0.5 mg is safe and effective for treatment of anaphylaxis from subcutaneous allergen immunotherapy.