The following is a summary of “Administration of β-lactam antibiotics to patients with reported penicillin allergy in the emergency department,” published in the June 2023 issue of Emergency Medicine by Holmes, et al.

β-lactam antibiotics are commonly prescribed in the Emergency Department (ED) for empiric sepsis therapy. However, patients with reported penicillin (PCN) allergies often receive inferior therapeutic options. In the United States, a significant portion of the population reports PCN allergies, but only a small percentage experience IgE-mediated reactions. For a study, researchers sought to evaluate the frequency and outcomes of patients in the ED with reported PCN allergies who were challenged with β-lactam antibiotics.

A retrospective chart review was conducted for patients aged ≥18 in the ED of an academic medical center between January 2015 and December 2019. Only patients who received a β-lactam despite reporting a PCN allergy were included. Patients who did not receive a β-lactam or did not report a PCN allergy before administration were excluded. The primary outcome was the frequency of IgE-mediated reactions in response to β-lactam administration. A secondary outcome assessed the frequency of continuing β-lactam treatment upon admission from the ED.

A total of 819 patients were included in the study, with 66% female. These patients had prior reported penicillin (PCN) reactions, which included hives (22.5%), rash (15.4%), swelling (6.2%), anaphylaxis (3.5%), and other symptoms (12.1%). In 40.3% of cases, the PCN reaction was undocumented in the medical electronic record. Interestingly, none of the patients experienced an IgE-mediated reaction to the β-lactam antibiotics administered in the Emergency Department (ED). Moreover, the previously reported PCN allergies did not significantly affect the continuation of β-lactam treatment when patients were admitted or discharged (OR: 1, 95% CI: 0.7–1.44). Notably, among patients with a history of IgE-mediated penicillin allergy, a substantial proportion (77%) were continued on a β-lactam after being discharged or admitted to the hospital from the ED.

In patients with previously reported PCN allergies, β-lactam administration did not result in IgE-mediated reactions, and there was no increase in adverse reactions. The study added to the growing evidence supporting the administration of β-lactams to patients with documented PCN allergies, suggesting that the reported allergy status may not be a barrier to using these antibiotics in the ED setting.

Source: sciencedirect.com/science/article/abs/pii/S0735675723001286