Abstract
Background: The number of patients who use an adrenaline auto-injector (AAI, Epipen®) is relatively small in Japan, with a usage rate of approximately 1% of the prescribed AAIs. Obtaining practical information on patients who have used these devices would be helpful to predict various scenarios that might occur during any emergency. Method: We retrospectively evaluated the detailed medical records of the patients who used an AAI. Results: There were 25 cases who used an AAI from August 2005 to December 2013. The situations of the causative intake were eating at a restaurant or purchased products (n=10), school lunch (n=8) and oral immunotherapy (n=7). At the time of discovery, about 70% of the cases were presenting with Grade 1-2 on the anaphylaxis grading classification, and only 28% of the cases were discovered with Grade 4 symptoms. The median time between discovery and AAI usage was 20 minutes (0-300 minutes), and was generally less than one hour. Discussion: The cases with absolute indications for AAI use at the onset were limited, and, in many cases, the symptoms progressed to the indication level after discovery. At the time of prescription, it is important for physicians to instruct patients on a systematic approach to treatment, including frequent evaluation of the symptoms, in order to ensure the appropriate timing of injection.
