Trend of oral antimicrobial use after removal of broad-spectrum antimicrobials from the formulary at a pediatric primary emergency medical center.

Introduction: While the effects of the Japanese action plan formulated in 2016 have gradually appeared, the appropriate use of antimicrobials in outpatient settings is still important. We conducted a previous study to recommend appropriate antimicrobial use via monthly newsletters at a pediatric primary emergency medical center (PEC). As a result, the rate of inappropriate prescription of oral third-generation cephalosporins (3GCs) decreased by 67.2%. This decrease prompted our institution to change the antimicrobials adopted from 3GCs to first-generation cephalosporins. There have been no reports on the prescribing trend of narrow-spectrum antimicrobials after the discontinuation of 3GCs in pediatric PECs.

Methods: We conducted a single-center, observational study at one pediatric PEC between April 2020 and March 2022. We recorded the total number of patients and oral antimicrobial prescriptions, diagnoses, and descriptions of the electronic health records and evaluated the prescription trends and appropriateness of antimicrobial use after removal of cefditoren-pivoxil and fosfomycin from the formulary.

Results: The total number of patients was 22,744 during the study period, and antimicrobials were prescribed to 496 (2.2%) patients. The proportion of amoxicillin prescriptions among total antimicrobials was high (53.4%). For each prescription, 85 of 259 prescriptions (32.8%) for amoxicillin, 161 of 185 prescriptions (87.0%) for cephalexin, and 17 of 43 prescriptions (39.5%) for clarithromycin were judged to be appropriate.

Conclusion: We suggest that after the removal of broad-spectrum antimicrobials and achieving a reduction in the prescription rate of oral antimicrobials, it is necessary to evaluate whether narrow-spectrum antimicrobials are used properly in pediatric PECs.