171 - Effectiveness and Feasibility of Pharmacist-Driven Penicillin Allergy De-Labeling Pilot Program

Background: Prevalence of true hypersensitivity to penicillins is low (0.5-2%). Documented penicillin allergies have been associated with an increased risk of adverse outcomes, including methicillin resistant Staphylococcus aureus infections, Clostridioides difficile infections, and surgical site infections. “De-labeling” of inappropriately documented allergies can decrease the use of unnecessary broad-spectrum antibiotics and prevent negative outcomes, but labor-intensive skin testing and oral challenges can be a barrier to program implementation. The goal of this project is to assess the effectiveness and feasibility of a pharmacist-led penicillin allergy de-labeling process that does not involve skin testing or oral challenges.

Methods: Adult patients with penicillin allergies were identified using a report within the electronic health record during a 3-month pilot period. Patients identified were interviewed by an infectious diseases pharmacy resident, and an allergy history was assessed utilizing a standardized checklist. The patients’ answers determined the ability to de-label via pharmacist utilization of an evidence-based and standardized checklist developed for this project. All documentation included a detailed patient allergy history along with a beta-lactam cross-reactivity chart to help guide future antibiotic choices.

Results: 66 patients were interviewed during the pilot. 12 patients (18%) met criteria for de-labeling and consented to the removal of the allergy. 4 patients (6%) met criteria for de-labeling but declined the removal of the allergy. Average time spent during patient interview was 5.2 minutes per patient. 58.3% of patients (7/12) who were de-labeled were subsequently prescribed a beta-lactam, and 100% (7/7) were able to tolerate the agents. 1 out of 4 patients (25%) who declined de-labeling but had their allergy updated to reflect intolerance was prescribed beta-lactams and was able to tolerate the agents (1/1, 100%).

Conclusion: A pharmacist-led penicillin allergy de-labeling process utilizing a standardized checklist is an effective method for removing penicillin allergies in patients who do not have a true allergy to penicillins.  This pharmacist-led process is a feasible method for sites unable to perform oral challenges or skin testing.