[Translated article] Evaluation of penicillin allergy labeling in the emergency department: Retrospective study on the impact of a hospital pharmacist-led intervention algorithm

Abstract

Objective: To evaluate the impact of an intervention algorithm on penicillin allergy label reassessment in emergency department patients, aiming to optimize antibiotic selection and improve patient safety.

Methods: A retrospective observational study was conducted in a 450-bed hospital, including adult patients with a penicillin allergy label admitted to the emergency department between November 2023 and August 2024. An algorithm developed by the pharmacy service in collaboration with the ASP team was applied, based on validated tools such as the Penicillin Allergy De-Labelling Toolkit, PEN-FAST, and Antibiotic Allergy Assessment Tool. Demographic data, allergy history, and clinical outcomes were collected. The acceptance of recommendations and the incidence of adverse reactions were analyzed.

Results: A total of 66 patients were evaluated. Delabeling was proposed in 35 (53.03%) patients, skin testing in 13 (19.69%), oral provocation testing in 9 (13.63%), and label maintenance in 9 (13.63%). A total of 89.39% of the recommendations were accepted, achieving effective delabeling in 42 patients. No adverse reactions were recorded. In 21 cases, antibiotic therapy was optimized following the intervention.

Conclusions: The implementation of a structured algorithm for penicillin allergy reassessment in emergency settings is both effective and safe. Its application facilitates antibiotic optimization, improves patient safety, and reduces broad-spectrum antibiotic use. This study highlights the role of hospital pharmacists in drug allergy management and antimicrobial stewardship.

Keywords: Alergia a penicilina; Emergency service; Farmacéutico hospitalario; Hospital pharmacist; Hospital pharmacy service; Penicilina; Penicillin; Penicillin allergy; Servicio de farmacia hospitalaria; Servicio de urgencias.