Nationwide epinephrine auto-injector dispensing in Greece: a drug-utilization study providing insights into anaphylaxis epidemiology and emergency-treatment preparedness.

Abstract

Background: Anaphylaxis is a serious systemic hypersensitivity reaction requiring prompt recognition and treatment, yet diagnosis-linked national surveillance is unavailable in many countries. Epinephrine auto-injector (EAI) dispensing cannot identify confirmed events or individual patients, but it is an epidemiologically relevant medication-use endpoint because EAIs are supplied to people with prior anaphylaxis or a clinically judged risk of future anaphylaxis.

Objective: To quantify nationwide EAI dispensing in Greece as a drug-utilization and emergency-treatment-preparedness benchmark and, secondarily, derive scenario-based incidence-compatible and prevalence-equivalent indicators relevant to the epidemiology of anaphylaxis.

Methods: This nationwide retrospective drug-utilization study analyzed aggregated net Anapen® DUO pack counts from reimbursed and non-reimbursed retail and hospital pharmacy channels during March 2015-March 2017, when it was the only EAI marketed nationally. Directly observed pack flow was primary, utilization by EAI strength was analyzed at the population level using age-equivalent denominators, expiry timing was examined conditionally, and scenario outputs were deterministic sensitivity analyses.

Results: During 25 months, 33,986 twin-packs were recorded (153.2 packs per 100,000 person-years). The final 12-month rate was 154.0 per 100,000 population. Using age-equivalent population denominators, 150-microgram dispensing intensity was 5.8-fold higher than 300-microgram intensity. Reference scenarios yielded an incidence-compatible anaphylaxis indicator of 47.7-125.3 episodes per 100,000 person-years and prevalence-equivalent active EAI coverage of 51.7-133.0 persons per 100,000. Deliberately broader assumption ranges widened these to 17.0-229.8 and 19.7-177.3, respectively.

Conclusion: Nationwide EAI dispensing provides the first all-age benchmark of access to community emergency epinephrine in Greece. By combining observed pack flow with transparent scenario-based analyses, this study introduces a reproducible approach for gaining insights into anaphylaxis epidemiology and emergency-treatment preparedness from national dispensing data, particularly where comprehensive registries are unavailable.