Successful penicillin allergy de-labelling

Approximately 10% of inpatients are labelled as ‘allergic to penicillin’ but the vast majority have not experienced a true allergic reaction. Having a penicillin allergy label can results in patients receiving sub-optimal alternative antibiotics and this may lead to poorer outcomes and increased costs. Moreover, patients with a history of low-risk allergy can safely be offered a supervised oral challenge to determine their true penicillin allergy status.

Hegarty and colleagues described the introduction of a penicillin allergy de-labelling service in Cavan and Monaghan Hospital, Ireland.¹ In addition to penicillin allergy de-labelling, the project set out to improve documentation of all medication allergies in patient records.

The Antimicrobial Stewardship (AMS) pharmacists adapted the Scottish Antimicrobial Prescribing Group (SAPG) penicillin allergy toolkit, complying with local governance requirements. This toolkit is designed to be used by non-allergy specialists and supports the identification and removal of penicillin allergy labels in patients who do not have a history of Type 1 or Type 4 hypersensitivity reactions. They also undertook a wide-ranging education campaign on the toolkit and on penicillin allergy awareness.  This included using grand rounds, medical, surgical and ED journal clubs, pharmacy meetings, clinical nurse manager meetings and ward safety pauses.

The results showed that during the period October 2022 – July 2023 61 patients were screened. 37 were deemed eligible for de-labelling and 34 were successfully de-labelled. Of these, 20 were de-labelled in accordance with the protocol (oral challenge); 12 did not require oral challenge “as they were deemed no more likely to have a penicillin allergy than another member of the population”. Two were not de-labelled in accordance with the approved protocol (both were receiving penicillin when reviewed).

Completion of the drug allergy section on the medical records increased from 80% to 100%.  Documentation of the nature of the adverse drug reaction increased from 14% to 27% for patients with a documented penicillin allergy. Both succeeded in the aim of achieving a 10% improvement.

The authors concluded that progress had been made but further improvements were possible as there were still considerable variations in staff engagement.

Reference

1. Hegarty M, Martin D, McKenna A, Caceda B, Trautt E, Daly R. Penicillin allergy awareness and de-labelling. (Poster) EAHP Congress 2025