Penicillin allergy de-labeling – Is it effective in the long term?

Published online: May 22, 2018

Penicillins are among the most common drug allergies reported worldwide. However, after allergy evaluation, less than 5% of the patients labeled are in fact allergic. Unverified penicillin allergy label has negative health implications. For this reason, it is important to remove these allergy labels whenever possible. The evaluation process of penicillin allergy usually requires performing a skin test (ST) and an oral challenge test (OCT) with the culprit drug.

In a study recently published in The Journal of Allergy and Clinical Immunology: In Practice, Lachover-Roth and colleagues evaluated the long-term outcomes of penicillin allergy de-labeling, by examining the re-use of penicillins, new allergic reactions after re-using, and whether the allergy label has been removed from the patient’s medical files.

OCT was conducted on 741 patients and completed uneventfully by 654 (88%) of them. Data was collected from medical records and/or telephone survey on 639 (97.7%) of those patients. Most patients (70%) had subsequently used penicillins at least once since the de-labeling. Mild adverse reactions were reported in 5.5% of the patients, who re-used penicillin. The main reason for not re-using penicillins was "lack of indication." When those patients were asked about future intention to use penicillins, if indicated, 93.2% of them expressed willingness to use it. Regarding the allergy label, more than half of the patients (51.37%) who completed the OCT uneventfully, still had a penicillin allergy label in their electronic medical file.

This study has found penicillin allergy de-labeling to be effective in the long term. Most of the patients re-used penicillins safely. Furthermore, patients who avoided penicillins due to lack of indication, expressed their readiness to use it in the future. However, in terms of allergy label modifications, there seems to be a discrepancy between the allergy evaluation and its documentation in patients' electronic medical files.

The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.

Close-up of pine tree branches in Winter Close-up of pine tree branches in Winter