Antibiotic use after removal of penicillin allergy label

BACKGROUND: Penicillin allergy is commonly reported in the pediatric emergency department. We previously performed 3-tier penicillin allergy testing on children with low-risk symptoms, and 100% tolerated a penicillin challenge without an allergic reaction. We hypothesized that no serious allergic reactions would occur after re-exposure to penicillin and that prescription practices would change after testing. METHODS: We performed a follow-up case series of 100 children whose test results were negative for penicillin allergy. Research staff administered a brief follow-up phone survey to the parent and primary care provider of each patient tested. We combined the survey data and summarized baseline patient characteristics and questionnaire responses. We then completed a 3-tier economic analysis from the prescription information gathered from surveys in which cost savings, cost avoidance, and potential cost savings were calculated. RESULTS: A total of 46 prescriptions in 36 patients were reported by the primary care provider and/or parents within the year after patients were tested for penicillin allergy. Twenty-six (58%) of the prescriptions filled were penicillin derivatives. One (4%) child developed a rash 24 hours after starting the medication; no child developed a serious adverse reaction after being given a penicillin challenge. We found that the cost savings of delabeling patients as penicillin allergic was §1368.13, the cost avoidance was §1812.00, and the total potential cost savings for the pediatric emergency department population was §192 223.00. CONCLUSIONS: Children with low-risk penicillin allergy symptoms whose test results were negative for penicillin allergy tolerated a penicillin challenge without a severe allergic reaction developing. Delabeling children changed prescription behavior and led to actual health care savings.