Drug and Alcohol Dependence 86 (2007) 167–174 Substance use among high-school students in southern Thailand: Trends over 3 years (2002–2004) Sawitri Assanangkornchai * , Uraiwan Pattanasattayawong, Nisan Samangsri, Anocha Mukthong Prince of Songkla University, Faculty of Medicine, Department of Psychiatry, 15 Kanchanavanich Road, Hat Yai, Songkhla 90110, Thailand Received 4 October 2005; received in revised form 8 May 2006; accepted 1 June 2006 Abstract Purpose: To examine the trends of substance use and correlated variables in high-school students in Southern Thailand. Methods: Surveys of high-school years 7, 9 and 11 and vocational school year 2 students in four provinces in Southern Thailand were conducted in 2002–2004 to examine lifetime substance use, use within 1 year and 30 days before the interview, using a self-completed questionnaire. Results: The prevalence of lifetime use of any illicit substance was 5–7% overall (about 7%, 9% and 13% in boys and 2%, 1% and 3% in girls in 2002, 2003 and 2004, respectively). Krathom, a local addictive plant, and cannabis were the most commonly used illicit substances on a lifetime basis with prevalences of 2.3%, 2.8%, 4.9% (p < 0.01) and 2.6%, 2.3%, 3.4% (p > 0.05) in the surveyed years. The rates of alcohol consumption in the past 30 days were 19.3%, 17.3% and 15.2% (p > 0.05) while smoking rates were 14.6%, 8.8% and 10.8% (p < 0.05). The significant correlates of current illicit substance use were surveyed year, male, vocational school, school level, and school performance. Conclusion: The problem of substance abuse is increasing among Thai adolescents. School-based interventions seem desirable, especially in boys, vocational and public school students. © 2006 Elsevier Ireland Ltd. All rights reserved. Keywords: Trends; Substance use; High-school students; Southern Thailand 1. Introduction As in many other countries, concern has been expressed in Thailand about an apparent increase in substance abuse prob- lems in school children. This concern has emanated from several sources, especially parents, schoolteachers and the police, and has been given wide publicity in the public media. Surveys of stu- dents in 2001 and 2002 revealed that the percentages of teenagers involved with experimenting with illicit substance use seemed to be increasing. The numbers of students from year 6 to univer- sity who had a lifetime use of any kind of substances (excluding alcohol and cigarettes) were estimated to be 374,653 (6.2% of all students) in 2001 and 413,725 (7.0%) in 2002 (ABAC-KSC Internet Poll, 2002). Cannabis was the most common drug used by these students, followed by methamphetamine (known as Yaba in Thailand), volatile substances and ecstasy. In a review of studies on risk and protective factors in Thai- land, the common reasons given for using substances were * Corresponding author. Tel.: +66 74 451351; fax: +66 74 429922. E-mail address: savitree.a@psu.ac.th (S. Assanangkornchai). persuasion by friends, behaving like others in a group, seeking novelty, living in an environment where controlled substances are readily accessible, and relationship problems in the family (Assanangkornchai, 2004). The study of substance use in South- east Asia, including Thailand in the Global Initiative Project on Primary Prevention of Substance Abuse in 1997 found that social pressure towards substance use was strengthened by the attitudes of young people towards such use, notably perceptions of social approval of substance use, the belief that substance use does not entail risks and that its usage is gratifying, lim- ited social censure, and ready availability of substances (World Health Organization, 2003). To date, most research on the extent of the substance abuse problem in Thai young people has been cross-sectional and has only provided information on selected groups at specific times (Piyasil and Meemarayatr, 1998; Ruangkanchanasetr et al., 2005). These studies used different definitions of substance use/abuse, thus making comparisons difficult. No long-term study in this population group has been carried out and no trends concerning changes in the problem have been reported. The cur- rent project, conducted by the Drug and Alcohol Research Group at Prince of Songkhla University in Southern Thailand, aimed 0376-8716/$ – see front matter © 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.drugalcdep.2006.06.001