D3.47 - Implementing Penicillin Delabelling in an Inpatient setting

Penicillin allergy is over-diagnosed, leading to suboptimal antibiotic use and increased healthcare costs. Traditionally, resource-intensive outpatient allergy testing is required for delabelling. Despite recent BSACI guidance helping to identify patients suitable for a direct oral challenge, NHS infrastructure has limited its application. This project aimed to bridge the gap by introducing an allergist-led inpatient delabelling pathway, supported by an infectious diseases (ID) pharmacist. to identify low-risk inpatients suitable for direct oral challenges (DOC), reducing outpatient burdens.

From August to December 2024, weekly allergist-led ward rounds were conducted. Patients were triaged to DOC, delabelling based on history alone, or referral for skin testing. DOC was performed on the ward under supervision, focusing on patients with childhood or remote (>10 years) reactions, typically rashes or unknown symptoms not requiring medical attention. The ID pharmacist conducted concurrent rounds with remote allergist input.

Of 77 patients identified for allergist-led rounds, 47 (61%) were reviewed. Among these, 25 (53%) were deemed suitable for DOC, with 22 (88%) successfully challenged whilst 3 (12%) declined. Seven (15%) were delabelled based on history alone, and 15 (32%) were referred for skin testing. No adverse reactions occurred.

In the pharmacist-led rounds, 38 additional patients were reviewed. Of these, 27 (69%) were delabelled based on history, 7 (18%) underwent successful DOC, 3 (9%) declined and 1 (3%) was referred for further testing.

This combined allergist- and pharmacist-led pathway safely delabelled 63 (54%) patients, reducing outpatient clinic burdens, supporting antimicrobial stewardship, and enabling timely use of first-line antibiotics. However, logistical challenges, including patient availability and ongoing medical issues, limited the efficiency of ward-based reviews. Future steps include addressing these barriers and the implementation of a targeted questionnaire that facilitates remote allergist input, empowering ward doctors to perform appropriate challenges at their convenience with close oversight from the allergists. This approach aims to streamline the process, build confidence among non-allergists, and further enhance the efficiency and accessibility of penicillin allergy delabelling.