Epinephrine autoinjector prescription patterns for severe anaphylactic patients in Japan: A retrospective analysis of health insurance claims data.

BACKGROUND

Current guidelines recommend that any patient who has experienced anaphylaxis should be prescribed one or more epinephrine autoinjectors (EAI) for immediate self-treatment. However, the etiology of anaphylaxis and prescription patterns of EAI have not been widely examined in Japan.

METHODS

This was a retrospective cohort study using a large Japanese claims database (JMDC, Tokyo, Japan). We included patients with severe anaphylaxis who received epinephrine in a hospital or outpatient clinic from 2011 to 2016. We extracted patients who were prescribed EAIs and examined the annual trend of EAI prescription rates and refill patterns.

RESULTS

We identified 1255 eligible patients. Among them, 361 patients (28.8%) were prescribed EAIs within 30 days after their initial severe anaphylactic episode. In patients who were prescribed EAIs, 65.9% were prescribed EAIs from the same facility in which initial treatment was given for severe anaphylaxis. The prescription rates of EAI significantly increased from 11.1% in 2011 to 30.9% in 2016. Among patients with initial EAI prescriptions, 97.3% refilled their EAI prescriptions at least once and 40.5% refilled their prescriptions annually during the 3 year follow up period.

CONCLUSIONS

EAI prescription rates were relatively low in patients who experienced severe anaphylaxis in Japan. Physicians should prescribe EAIs to all patients who were treated for anaphylaxis under their care and avoid delegating the responsibility of prescribing EAIs to other facilities. Initial prescription of EAIs can result in improved regular refill and dissemination practices.