East Asian Arch Psychiatry 2016;26:43-4


Drug Addiction: A Global Challenge

pdf Full Paper in PDF

Drug addiction is characterised by compulsive, uncontrollable drug use irrespective of its negative consequences.1 It has been recognised as a chronic disease with high possibility of relapse inflicting far-reaching psychological and physical damage on sufferers.2 Over the past decade, the prevalence of illicit drug use has been stable at around 0.5% of the population globally but it varies by country / region and types of drugs.2 East and South- East Asia are a hub for manufacturing and shipping of illicit drugs.2 Methamphetamine use, for example, shows an increasing trend in East Asia though it is stable elsewhere. Regular monitoring of illicit drug use is essential to inform and guide local anti-drug campaigns. In this issue, Ren et al3 have provided an excellent overview of the status of drug abuse in East Asia.

Dysfunction of dopaminergic neurotransmission is a critical biological marker for drug addiction. In the early 1990s, a unique gene variant, the A1 allele in dopamine D2 receptor gene, was found in patients with alcoholism.4

Later, further gene variants of dopamine receptors, transporter or other regulator genes were discovered related to low dopaminergic receptor function5 and low dopamine release.6 Deficient dopaminergic functions could result in a blunted response to reward stimuli7 and increased “pleasure” feeling to stimulants,8 indicating vulnerability to drug addiction. Low striatal dopamine functions have been consistently identified in patients addicted to almost all types of substances that mainly affect the striatal dopamine level.7,9 Striatal dopaminergic functions, therefore, have been considered a treatment target for drug addiction. Nonetheless, earlier attempts with agents that act directly on striatal dopamine receptors were either ineffective or had high potential for abuse themselves. Along with a deeper understanding of the Daedalean interactions between dopamine and other neurotransmitters, such as glutamate and gamma-aminobutyric acid,10 many new compounds that bind to non-dopamine or atypical dopamine sites have recently been developed. These emerging agents together with other non-pharmacological treatments are reviewed by Davidson11 in this issue.

Drug addiction is a very complex biologically and psychosocially determined condition. Environmental factors (e.g. childhood maltreatment or other stressful life events) can modify the genetic risk of drug addiction. For example, adverse childhood experiences may predispose the genetically susceptible individual to drug addiction while a harmonious childhood and development is protective.12-14 Environmental risk factors can further drive drug misuse through early life to adulthood.14 Psychosocial therapies that cultivate skills and an ability to cope with negative environmental factors are useful adjuncts in the treatment of drug addiction.15 In a longitudinal study, Cheung et al16 identified a series of psychosocial factors that encourage or ameliorate continuous drug use; the study also provides valuable information for psychosocial interventions in drug addiction.

Exploring the effectiveness of traditional medicine or folk remedies for drug addiction is gaining momentum. To date, the effectiveness of traditional herbal medicines has nonetheless not been confirmed.17 Acupuncture has been thoroughly studied in the relief of withdrawal symptoms in the detoxification stage of heroin and nicotine addiction and may be effective when integrated with other treatment modalities.18 Wu et al19 in this issue discussed electrical acupuncture in the treatment of opioid addiction and its mechanism of action. Despite the advances made in the treatment of drug addiction that are summarised in this issue, more work needs to be done to gain a better understanding of its pathophysiology to aid in the development of new forms of treatment.

Hua-Jun Liang, MD, PhD
Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong SAR, China

Yong Lin, MD, MPhil
Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong SAR, China

Chenxi Zhang, MD, MPhil
Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong SAR, China

Gabor S. Ungvari, MD, PhD 
School of Psychiatry & Clinical Neurosciences, University of Western Australia, Perth, Australia University of Notre Dame Australia / Marian Centre, Perth, Australia

Wai-Kwong Tang, MD, PhD (Email: tangwk@cuhk.edu.hk)
Department of Psychiatry, The Chinese University of Hong Kong, Hong Kong SAR, China


  1. Malenka RC, Nestler EJ, Hyman SE. Charter 15: Reinforcement and addictive disorders. In: Sydor A, Brown RY, editors. Molecular neuropharmacology: A foundation for clinical neuroscience. 2nd ed. New York: McGraw-Hill Medical; 2009:364-8.
  2. United Nations Office on Drugs and Crime. World drug report 2015. United Nations publication, Sales No. E.15.XI.6.
  3. Ren Q, Ma M, Hashimoto K. Current status of substance abuse in East Asia and therapeutic prospects. East Asian Arch Psychiatry 2016;26:45-51.
  4. Blum K, Noble EP, Sheridan PJ, Montgomery A, Ritchie T, Jagadeeswaran P, et al. Allelic association of human dopamine D2 receptor gene in alcoholism. JAMA 1990;263:2055-60.
  5. Pohjalainen T, Rinne JO, Någren K, Lehikoinen P, Anttila K, Syvälahti EK, et al. The A1 allele of the human D2 dopamine receptor gene predicts low D2 receptor availability in healthy volunteers. Mol Psychiatry 1998;3:256-60.
  6. Casey KF, Benkelfat C, Cherkasova MV, Baker GB, Dagher A, Leyton M. Reduced dopamine response to amphetamine in subjects at ultra- high risk for addiction. Biol Psychiatry 2014;76:23-30.
  7. Trifilieff P, Martinez D. Blunted dopamine release as a biomarker for vulnerability for substance use disorders. Biol Psychiatry 2014;76:4-5.
  8. Volkow ND, Wang GJ, Fowler JS, Thanos PP, Logan J, Gatley SJ, et al. Brain DA D2 receptors predict reinforcing effects of stimulants in humans: replication study. Synapse 2002;46:79-82.
  9. Blum K, Sheridan PJ, Wood RC, Braverman ER, Chen TJ, Cull JG, et al. The D2 dopamine receptor gene as a determinant of reward deficiency syndrome. J R Soc Med 1996;89:396-400.
  10. Ross S, Peselow E. The neurobiology of addictive disorders. Clin Neuropharmacol 2009;32:269-76.
  11. Davidson C. Developing treatments for stimulant abuse: a brief overview. East Asian Arch Psychiatry 2016;26:52-9.
  12. Enoch MA. Genetic and environmental influences on the development of alcoholism: resilience vs. risk. Ann N Y Acad Sci 2006;1094:193- 201.
  13. Sweitzer MM, Halder I, Flory JD, Craig AE, Gianaros PJ, Ferrell RE, et al. Polymorphic variation in the dopamine D4 receptor predicts delay discounting as a function of childhood socioeconomic status: evidence for differential susceptibility. Soc Cogn Affect Neurosci 2013;8:499-508.
  14. Hicks BM, South SC, Dirago AC, Iacono WG, McGue M. Environmental adversity and increasing genetic risk for externalizing disorders. Arch Gen Psychiatry 2009;66:640-8.
  15. Kleber HD, Weiss RD, Anton RF Jr, George TP, Greenfield SF, Kosten TR, et al. Treatment of patients with substance use disorders, second edition. Am J Psychiatry 2007;164(4 Suppl):5-123.
  16. Cheung NW, Cheung YW, Chen X. Permissive attitude towards drug use, life satisfaction, and continuous drug use among psychoactive drug users in Hong Kong. East Asian Arch Psychiatry 2016;26:60-9.
  17. Lu L, Liu Y, Zhu W, Shi J, Liu Y, Ling W, et al. Traditional medicine in the treatment of drug addiction. Am J Drug Alcohol Abuse 2009;35:1- 11.
  18. Margolin A. Acupuncture for substance abuse. Curr Psychiatry Rep 2003;5:333-9.
  19. Wu SL, Leung AW, Yew DT. Acupuncture for detoxification treatment of opioid addiction. East Asian Arch Psychiatry 2016;26:70-6.
View My Stats