Safety of herbal medicine for elderly patients with chronic disease in the Republic of Korea

Introduction: Elderly patients with chronic diseases may experience unintended adverse events (AEs) related to medication. This study investigated the detection of drug safety signals associated with herbal medicine by analyzing spontaneous AE reports in this patient group to generate new safety information. Methods: The "Korea Institute of Drug Safety and Risk Management Korea Adverse Event Reporting System database (KIDS-KD)" was used to investigate patients over 65 years old with chronic disease from 2013 to 2016. The target of analysis is seven herbal medicines such as ginkgo leaf extracts, ivy leaf extracts, herbal cough suppressants and expectorants. AEs associated with herbal medicine were considered a signal if they accounted for greater than 0 of the 95% lower confidence interval of the Information Component (IC025). The relevance of unexpected Adverse Drug Reactions (ADRs) was determined based on a review of the KIDS-KD and then derived as safety information. Results: Among 113 types of herbal medicine-AE combinations, 56 drug-event combinations (DECs) in elderly patients with chronic disease were detected as signals. Of those, 12 types of DEC5 were investigated as unexpected ADR and finally 9 types were assessed as necessitating reporting of safety information: ginkgo leaf extracts (depression, thrombocytopenia), ivy leaf extracts (bullous eruption, muscle weakness, nocturia, lip ulceration, neuropathy peripheral, anxiety, malaise). Conclusions: The elderly have a high prevalence of chronic diseases, resulting in polypharmacy, and potentially creating a high risk of ADRs. Establishing a pharmacovigilance system for herbal medicine is of great importance.