Retrospective analysis of adverse drug reaction patterns from the national monitoring system in a tertiary care hospital in China (2019-2024).

Objectives: To characterize the patterns, risk factors, and reporting trends of adverse drug reactions (ADRs) in a tertiary care hospital in China to inform targeted medication safety interventions. Methods: A single-center, retrospective analysis was conducted on 5,564 ADR reports extracted from the National Adverse Drug Reaction Monitoring System (2019-2024). Reports were assessed for causality using the WHO-UMC criteria. Descriptive statistics and chi-squared tests were employed to analyze demographics, reporting trends, causative drugs, administration routes, and clinical outcomes. Results: The mean patient age was 62.4 years, with males slightly predominating (52.5 %). ADR reporting increased markedly over the study period, with pharmacists becoming the primary reporters (93.1 % in 2024). Intravenous infusion was the most common route (67.3 %). Antineoplastic agents were the predominant drug class implicated (34.2 %), followed by anti-infectives (10.8 %) and cardiovascular drugs (9.4 %). Statistically significant associations were found between ADR outcomes and both the type of ADR (new/serious vs. general, p<0.001) and the administration route (intravenous vs. oral, p<0.001). No significant association was observed between patient age and ADR outcomes (p=0.244). Conclusions: Antineoplastic drugs and intravenous administration are key ADR risk factors. Enhanced monitoring of high-risk medications and optimized infusion protocols are needed. Limitations include retrospective single-center design and reporting biases.