# Effectiveness, barriers, and facilitating factors of strategies for active delabeling of patients with penicillin allergy labels: a systematic review

## TL;DR

This study reviews strategies to remove incorrect penicillin allergy labels in hospitalized patients and identifies effective methods and barriers to their implementation.

## Contribution

The paper systematically evaluates delabeling strategies for penicillin allergy and identifies facilitators and barriers to their implementation.

## Key findings

- Skin testing had the highest success rate (87%) for delabeling incorrect penicillin allergies.
- Interdisciplinary team involvement and standardized algorithms facilitated successful delabeling.
- Barriers included patient refusal, staff resistance, and financial limitations in smaller hospitals.

## Abstract

Penicillin allergy is the most frequently reported allergy in hospitalized patients, although rarely confirmed. Given the negative outcomes associated with incorrect penicillin allergy diagnoses, implementation of programmatic delabeling strategies is important for successful antibiotic stewardship. This systematic review evaluates the effectiveness of different delabeling strategies and highlights elements and settings that facilitate or constrict their implementation.

Following the PRISMA-statement PubMed/MEDLINE, EMBASE, Cochrane Library, and grey literature databases “Worldcat” and “OpenGrey” were searched for studies reporting on interventions to identify, evaluate, or rule out incorrect penicillin allergy in hospitalized adults. Data extraction included settings, intervention types, and their effectiveness, barriers, facilitators, and regulatory factors.

This review included 42 studies, involving 6269 patients undergoing penicillin allergy delabeling, with 5017 (80%) successfully delabeled. Effectiveness varied from 32% to 99%. Skin testing had the highest success rate at 87%, followed by a combination of skin testing and oral challenge (84%), and direct oral challenges (77%). Direct delabeling alone had a lower effectiveness (67%), which improved to 80% when paired with oral challenges. Key facilitators included standardized algorithms and involvement of interdisciplinary teams. Barriers included patient refusal, staff resistance, time constraints, and financial limitations, particularly in smaller hospitals.

Dependent on financial and staffing resources, oral challenges and direct delabeling after risk stratification may be alternatives to resource-intensive methods, such as skin testing, for successful delabeling. To address barriers to widespread delabeling implementation, patient and provider education must be improved, interprofessional collaboration enhanced, and standardized protocols developed.

The online version contains supplementary material available at 10.1007/s15010-025-02689-4.