Regulation and Decriminalisation of Illegal Substances in Thailand

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Rasmon Kalayasiri Teerayuth Rungnirundorn Robert Ali John Marsden


Psychoactive substances – chemical compounds which can alter a person’s mood, thoughts, and behaviors may be liable to misuse and cause addiction. Internationally, many strategies have been implemented in order to limit the supply and demand of illegal substances, with a wide variation at the country level. Thailand is an upper-middle income country in Southeast Asia. Since 2015, Thai authorities and policymakers have instituted many changes to the legal controls on illegal drugs. The aim of this review was to summarise the history of drug control and regulation in Thailand, focusing on opioids (including Kratom), methamphetamines and cannabis, and the outcome of recent strategies. Recent measures towards decriminalising substance use disorders are also discussed.


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Kalayasiri R, Rungnirundorn T, Ali R, Marsden J. Regulation and Decriminalisation of Illegal Substances in Thailand. Journal of Health Science and Medical Research [Internet]. 4Mar.2019 [cited 10Dec.2019];37(2):157-62. Available from:
Review Article


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