ORIGINAL ARTICLE HLA-B*1502 Strongly Predicts Carbamazepine-Induced Stevens–Johnson Syndrome and Toxic Epidermal Necrolysis in Thai Patients with Neuropathic Pain Kongkiat Kulkantrakorn, MD*; Wichittra Tassaneeyakul, PhD † ; Somsak Tiamkao, MD ‡ ; Thawinee Jantararoungtong, MSc † ; Napat Prabmechai, BSc † ; Suda Vannaprasaht, MD † ; Pansu Chumworathayi, MSc § ; Pei Chen, PhD ¶ ; Paskorn Sritipsukho, MD** *Department of Medicine, Faculty of Medicine, Thammasat University, Thailand; † Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Thailand; ‡ Department of Medicine, Faculty of Medicine, Khon Kaen University, Thailand; § Pharmacy Unit, Srinagarind Hospital, Faculty of Medicine, Khon Kaen University, Thailand; ¶ Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan; **Graduate Studies, Faculty of Medicine, Thammasat University, Thailand n Abstract: Background: Carbamazepine (CBZ) is one of the standard pharmacological treatments for neuropathic pain. How- ever, its serious adverse drug reactions include Stevens– Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Recently, HLA-B*1502 allele was implicated as a genetic marker of CBZ-induced SJS/TEN in some Asian epilepsy populations. Methods: This is a case control study to describe the clinical characteristics of SJS/TEN in Thai patients with neu- ropathic pain who were treated with CBZ, and to determine the association of HLA-B*1502 in these patients, comparing with those who exposed to CBZ for at least 6 months without any cutaneous reactions. Results: Thirty-four SJS/TEN patients and 40 control pati- ents were included in this study. Mean age of SJS/TEN Address correspondence and reprint requests to: Kongkiat Kulkant- rakorn, MD, Department of Medicine, Faculty of Medicine, Thammasat University, Klong Luang District, Pathumthani 12120, Thailand. E-mail: kongkiat1@gmail.com. Authors Contribution: KK, WT, ST contributed in study conception design and data acquisition, performed data analysis and interpretation, drafted and revised manuscript. KK was the primary author for this man- uscript and led manuscript preparation. WT applied funding and project management. TJ, NP, SV, PC involved in data acquisition, performed technical analysis, and interpretation of result. PC contributed in techni- cal analysis. PS contributed in data analysis, interpretation, drafting, and revising manuscript. All authors read and approved the manuscript. Submitted: February 4, 2011; Revision accepted: April 8, 2011 DOI. 10.1111/j.1533-2500.2011.00479.x Ó 2011 The Authors Pain Practice Ó 2011 World Institute of Pain, 1530-7085/11/$15.00 Pain Practice, Volume ••, Issue •, 2011 ••–••