Phytomedicine 18 (2011) 1208–1213 Contents lists available at ScienceDirect Phytomedicine jou rn al hom epage: www.elsevier.de/phymed Liver enzyme abnormalities during concurrent use of herbal and conventional medicines in Korea: A retrospective study Na-Hee Kim, Hwan-Yong Jung, Seung-Yeon Cho, Seong-Uk Park ∗ , Jung-Mi Park, Chang-Nam Ko Department of Cardiovascular & Neurologic Diseases, College of Oriental Medicine, Kyung Hee University, Seoul, Republic of Korea a r t i c l e i n f o Keywords: Concurrent Herb Conventional Liver Drug-induced liver injury (DILI) Hepatotoxicity a b s t r a c t Concurrent use of herbal medicine (HM) and conventional medicine (CM) is increasing. However, little is known about the prevalence of drug-induced liver injury (DILI) related to this concurrent use. In order to investigate changes in liver enzymes during concurrent use of HM and CM and to assess the prevalence of DILI related to their concurrent use, we screened for liver injury among inpatients at our institution who were administered both HM and CM for at least 14 days while hospitalized between 2006 and 2010. We used the Council for International Organization of Medical Science (CIOMS) laboratory criteria to define liver injury. Of the 892 patients included in the study, 34 (3.81%) had liver injury on admission and 21 (2.35%) had liver injury at discharge. Of the 48 cases that fulfilled the CIOMS laboratory criteria for liver injury, 34 had preexisting liver injury. The remaining 14 were analyzed, and five were concluded to have DILI, resulting in a prevalence of 5/892 (0.56%, with a 95% confidence interval of 0.07–1.05%). Overall, clinical symptoms of liver injury were mild. We thus contend that concurrent use of HM and CM is relatively safe. © 2011 Elsevier GmbH. All rights reserved. Introduction The rising use of herbal medicine (HM) has been documented by a number of studies (MacLennan et al. 2006; Eisenberg et al. 1998; Ness et al. 2005; Cheung et al. 2007) and has been accompa- nied by an increase in the concurrent use of HM and conventional medicine (CM) (Elmer et al. 2007). Although several observational studies have reported a low prevalence (0–0.97%) of HM-induced liver abnormalities (Mitsuma 2002; Mantani et al. 2002; Melchart et al. 1999a,b), there are currently no reports that examine liver function during concurrent use of HM and CM. Systematic investigation of the effects of concurrent HM and CM use on liver function is challenging for several reasons. First, each herbal preparation may contain various herbs, while each herb contains compounds that vary depending on the time and place of collection. Second, some ingredients of herbal preparations may interact with conventional drugs. Finally, the herb–drug combi- nations used by any single patient may have varying degrees of hepatotoxicity as well as the ability to produce an idiosyncratic drug reaction. ∗ Corresponding author at: Stroke & Neurological Disorders Center, Kyung Hee University Hospital at Gangdong, 149 Sangil-dong, Gangdong-gu, Seoul # 134-727, Republic of Korea. Tel.: +82 2 440 6217; fax: +82 2 440 6217. E-mail address: happyomd@khu.ac.kr (S.-U. Park). Given the rising use of both HM and CM, data regarding the prevalence of resulting drug-induced liver injury (DILI) is important for patients and practitioners alike. Although significant challenges have prevented systematic investigation of DILI during concurrent HM and CM use, pragmatic studies are needed in the short term to provide preliminary data to guide both patient behavior and clinical reasoning. In this study, we retrospectively reviewed changes in liver func- tion of inpatients being administered both HM and CM for more than 2 weeks. Methods Subjects Study subjects consisted of patients hospitalized at the Stroke and Neurological Disorders Center of Kyung Hee East-West Neo Medical Center between June 1, 2006 and April 16, 2010 who were concurrently administered HM and CM. Inclusion criteria were: (1) hospitalization for more than 14 days and (2) administration of both HM and CM. There were no exclusion criteria. Approval for clinical research was obtained from the KHNMC Institutional Review Board (KHNMC-OH-IRB 2010-008). 0944-7113/$ – see front matter © 2011 Elsevier GmbH. All rights reserved. doi:10.1016/j.phymed.2011.06.026