Changes in Pediatric Tetracycline Prescribing Patterns During the 2024 Mycoplasma pneumoniae Pneumonia Epidemic in the Republic of Korea.

BACKGROUND: Although macrolide-resistant Mycoplasma pneumoniae pneumonia prevalence exceeds 90% in the Republic of Korea, health insurance reimbursement policies historically restrict guideline-recommended tetracycline use in children aged <12 years. After a post-pandemic outbreak, reimbursement coverage was expanded in late 2023, and clinical guidelines were updated in early 2024 to permit tetracycline use in this age group. This study evaluated the impact of these policy changes on nationwide pediatric prescribing. METHODS: Using national prescription and sentinel surveillance data (2015-2025), an interrupted time-series analysis assessed changes in tetracycline prescribing responsiveness to epidemic intensity, with the intervention point set to March 2024. RESULTS: Pediatric tetracycline prescribing remained low until 2023 but increased markedly in 2024, with annual standardized prescribing rates (units per 1000 population) rising from <0.01 to 0.22, 0.01 to 0.74 and 0.91 to 1.74 in the 0-4, 5-9 and 10-14 year age groups, respectively. Before the intervention, prescribing showed no significant association with epidemic activity in any age group; after the intervention, significant synchronization emerged in children aged <15 years (P < 0.001). Prescribing rates lagged the initial epidemic rise by approximately 2 months but declined in parallel as the outbreak resolved. CONCLUSIONS: After the 2024 policy changes, tetracycline prescriptions rose and fell in sync with Mycoplasma pneumoniae pneumonia epidemic activity. This rapid de-escalation argues against persistent prescription drift and suggests active clinical judgment rather than passive exploitation of newly available access.