Suicidal use of East Asian traditional herbal medicine: A systematic review of observational studies and implications for regulation

Abstract

IntroductionSuicide attempts by consuming poisonous native plants are more frequent in Asia than in the West. In East Asian traditional medicine (EATM), herbal materials are routinely used as the primary treatment method; however, some medicinal herbs are toxic and can cause death. This review investigated the herbal materials used in EATM for suicide. MethodsFourteen databases were searched for articles published on suicidal use of EATM until September 7, 2022. Observational studies reporting the suicidal use of EATM herbal medicines were included. Study Quality Assessment Tools developed by the National Heart, Lung, and Blood Institute were used to assess methodological quality of included studies. Due to substantial heterogeneity a meta-analysis was not conducted and the results are narrated. ResultsNine case reports and one retrospective cohort study involving 81 patients were included in the analysis. One suicide attempt resulted in death, but all the other patients survived. The suicide attempts involved the use of topical medications, such as Red Flower Oil; herbal compositions, such as Kyushin and Niuhuang-Jiedu-Pian; and single herbs, such as Mylabris, Aconiti Tuber, Pruni Semen, and Ephedrae Herba. In most cases, gastrointestinal symptoms, an increase in the blood concentration of a specific substance, or an abnormal electrocardiography finding were reported. The methodological quality of included studies was generally poor. ConclusionAccess to toxic herbs that can be consumed to attempt suicide should be regulated through government-level management. Further research should be conducted to properly monitor and strategize safe use of herbal materials.