(also referred to as dependence syndrome, drug dependence, psychological dependence, or substance dependence) refers to a maladaptive pattern of behaviors and compulsive use of drugs despite harm. Addiction is distinct from analgesic tolerance or physical dependence, although the phenomena may co-occur (e.g., in heroin addicts). Neither analgesic tolerance nor physical dependence is sufficient to characterize addiction. Addiction is a biopsychosocial condition and evidence shows that it is not more common in patients with chronic pain from cancer than in the general population. Addiction is not a side effect, or an expected consequence, of opioid use.

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  7. Controlled Substances Act, 812, Schedules of controlled substances. 
  8. District Court of Appeal of Florida, Third District.676 So.2d 1380, June 26, 1996.
  9. World Health Organization. WHO expert committee on drug dependence: thirty-fourth report. Geneva, Switzerland: World Health Organization, 2006. (Available at

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