OBJECTIVE To explore the adverse drug reactions(ADRs) of vancomycin in children of different age groups and investigate their influencing factors based on real-world data.

METHODS A retrospective cohort study was conducted, selecting 1334 hospitalized pediatric patients who received vancomycin in the authors’ hospital from January 2010 to May 2025. Referring to the FDA Adverse Event Reporting System database, ADR monitoring data from Fujian Province and Xiamen City, the China Hospital Pharmacovigilance System was used to screen for cases of severe ADRs and ADRs. Incidence rates of known and new severe ADRs/ADRs in newborns, infants, and children were compared. The Logistic regression models were used to analyze the influencing factors.

RESULTS The ADR with a high incidence rate was blood and lymphatic system diseases. The highest incidence of severe ADR was hemoglobin reduction(123 cases, 9.22%), and the incidence in newborns was significantly higher than that observed in infants and children. several ewly identified ADRs were found including decreased blood pressure, disseminated intravascular coagulation, elevated lymphocytes, lymphadenopathy, hyperkalemia, hypoalbuminemia, tachycardia, etc. The analysis of the impact on the top 5 ADRs with high incidence rates and significant differences between groups(eosinophilia, red blood cell reduction, hemoglobin reduction, elevated gamma glutamyl transpeptidase, and tachycardia) showed that off-label drug use increased the risk of eosinophilia(OR=1.807, 95% CI: 1.128-2.896), and for every increase in the number of concomitant medications, the risk of eosinophilia, red blood cell reduction, elevated gamma glutamyl transpeptidase, and tachycardia increased by 1.7%, 2.5%, 2.4%, and 4.4%, respectively.

CONCLUSION Physician should pay attention to blood routine, liver function, and electrocardiogram monitoring when using vancomycin in children, especially in newborns. It is recommended to implement hierarchical risk management, involve clinical pharmacists in medication guidance, combine blood drug concentration monitoring for early warning, and optimize the combination of medication to improve the safety of vancomycin use.