Drug Utilization in Korean Neonatal Intensive Care Units: A Nationwide Cohort Study

Background :Neonates in neonatal intensive care units (NICUs) often undergo polypharmacy to support life-sustaining treatments and promote growth.This study aimed to characterize the use of pharmacologically active medications in Korean NICUs and to evaluate utilization patterns based on gestational age (GA) and birth weight (BW). Methods :This retrospective cohort study analyzed data from the Health Insurance Review and Assessment (HIRA) database covering the period from January 1, 2015, to December 31, 2019.Claims that included both NICU-related codes and prescriptions for pharmacologically active medications were included.Information on drug use for neonates was obtained from the U.S. Food and Drug Administration (FDA) and the Korean Ministry of Food and Drug Safety (MFDS).Results : Over five years, there were 135,893 claims, that included NICU-related codes and prescriptions for pharmacologically active medications.The mean number of medications per claim was 5.1 (median: 3), which increased significantly with decreasing GA (11.1 for GA < 28 weeks, 7.0 for GA 28-31 weeks, and 3.7 for GA 32-36 weeks; p < 0.0001) and BW (10.9 for BW < 1,000 g, 7.1 for BW 1,000-1,499 g, and 4.3 for BW 1,500-2,499 g; p < 0.0001).Systemic anti-infectives were the most frequently prescribed drug class (40.0%), followed by cardiovascular and nervous system agents.Notably, most medications lacked information for neonate use from the FDA (89.1%) or MFDS (91.7%). Conclusion :The findings reveal a significant therapeutic burden in neonates with lower gestational age and birth weight.Most medications used in NICUs lack guidance for neonatal use from the MFDS.These results