Reevaluating Penicillin Allergy Labels Reveals Low True Allergy Rates

A major clinical trial led by the University of Leeds and funded by the National Institute for Health and Care Research in the U.K. has found that 88% of individuals with a penicillin allergy specified in their medical records were not truly allergic, suggesting that widespread testing could improve infection treatment and help address antibiotic resistance.

Over 800 patients across 51 general practices in England participated in the ALABAMA trial, coordinated by the University of Oxford's Primary Care Clinical Trials Unit. Participants were randomly placed in an allergy-check group or a control group receiving standard care. Allergy tests involved either a small injection or oral dose of penicillin, followed by home monitoring. Serious reactions were not observed.

Penicillins are typically the first-choice antibiotics for many infections. However, labelled patients often receive alternative drugs that may be less effective, resulting in additional prescriptions, delayed recovery, and increased antimicrobial resistance. By removing inaccurate allergy labels, general practioners were found to be five times more likely to prescribe first-choice penicillin antibiotics.

Although the trial showed that penicillin allergy testing is effective and safe, access can be limited. Researchers are now working with health authorities to expand testing availability.

Jonathan Sandoe, joint leader author of the study published in Lancet Primary Care, noted the urgency of acting against rising resistance: “This research shows that removing incorrect penicillin allergy labels has the potential to improve patient experiences, reduce health costs and tackle bacterial resistance. Now, we need to work together with policymakers and patients to help the NHS to address this issue.”