Actions of delta-9-tetrahydrocannabinol in cannabis: relation to use, abuse, dependence

Int Rev Psychiatry. 2009 Apr;21(2):104-12. doi: 10.1080/09540260902782752.


Cannabis use disorders have been recently identified as a relevant clinical issue: a subset of cannabis smokers seeks treatment for their cannabis use, yet few succeed in maintaining long-term abstinence. The rewarding and positive reinforcing effects of the primary psychoactive component of smoked cannabis, delta-9-tetrahydrocannabinol (THC) are mediated by the cannabinoid CB1 receptor. The CB1 receptor has also been shown to mediate cannabinoid dependence and expression of withdrawal upon cessation of drug administration, a phenomenon verified across species. This paper will review findings implicating the CB1 receptor in the behavioural effects of exogenous cannabinoids with a focus on cannabinoid dependence and reinforcement, factors that contribute to the maintenance of chronic cannabis smoking despite negative consequences. Opioidergic modulation of these effects is also discussed.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Cannabis / chemistry*
  • Dronabinol / adverse effects*
  • Dronabinol / pharmacology*
  • Humans
  • Marijuana Abuse / etiology*
  • Marijuana Abuse / metabolism
  • Marijuana Abuse / psychology
  • Marijuana Smoking / psychology*
  • Receptor, Cannabinoid, CB1 / agonists*
  • Reinforcement, Psychology


  • Receptor, Cannabinoid, CB1
  • Dronabinol