Work

Safety of individualized herbal medicine for dysmenorrhea: pharmacovigilance from South Korea’s national pilot

Year: 2026

Type: article

Abstract: Background: In 2020, South Korea's National Health Insurance (NHI) began reimbursing individually prescribed herbal medicine decoctions (HMDs) for dysmenorrhea, highlighting the need for robust post-coverage safety monitoring using national claims data. Objective: To evaluate the safety of reimbursed HMDs for dysmenorrhea and demonstrate a claims-based pharmacovigilance approach to inform benefit management and clinical guideline integration. Methods: A retrospective cohort study was conducted using the Health Insurance Review & Assessment (HIRA) national claims database from 2015 to 2022. HMD users were coarsened-exact-matched to nonusers on sociodemographic and clinical characteristics. Difference-in-differences models compared pre- and post-coverage outcomes at 1, 3, 6, and 11 months. Primary outcomes were hepatotoxicity and renal failure; secondary outcomes included allergic reactions, emergency department visits and hospitalizations. Results: The matched cohort comprised 8,989 HMD users and 8,989 nonusers. Reimbursed HMDs were not associated with increased risk of severe adverse events at any time point. At 3 months, DID estimates were -2.6 (95% CI -411.8, 406.6) for hepatotoxicity and -7.2 (95% CI -402.3, 388.0) for renal failure, with consistent safety patterns across endpoints and sensitivity analyses. Conclusion: Coverage of individually prescribed HMDs under South Korea's NHI system was not associated with elevated serious safety risks for dysmenorrhea. These findings support continued reimbursement and provide a scalable template for claims-based pharmacovigilance using standardized endpoints, routine signal detection, and feedback to benefit design and clinical practice.

Source: Frontiers in Pharmacology

DOI: 10.3389/fphar.2026.1722249

Authors: Minjung Park, Yongjoo Kim, Nan-He Yoon, Kyeore Bae, Junhyeok Yi, Sujin Kim