Concurrent Disorders:

The presence of one or more primary, physical and/or psychiatric disorders that have an interactive effect on the course of Substance Dependence and require specific diagnosis and treatment in order to achieve stabilization and/or recovery. (Adopted Canadian Society of Addiction Medicine October 14, 1999)

Controlled Substance:

There are many controlled substances listed under the Controlled Substance Act. These drugs are grouped under schedules. Below are examples of some of the better known drugs within each Schedule:

  • Schedule I contains drugs made from the opium poppy such as heroin, codeine; drugs made from coca such as cocaine; and synthetically derived drugs such as methadone.
  • Schedule II contains cannabis (marijuana) and its derivatives.
  • Schedule III contains drugs such as amphetamines and lysergic acid diethylamide (LDS). 
  • Schedule IV contains drugs such as benzodiazepines and barbiturates.
  • Schedule V and VI contain precursors required to produce controlled substances (NationalAssociation of Pharmacy Regulatory Authorities, 2002-2004).


Methadone (also known as Symoron, Dolophine, Amidone, Methadose, Physeptone, Heptadon and many other names) is a synthetic opioid. It is used medically as an analgesic and a maintenance anti-addictive and reductive preparation for use by patients with opioid dependency. It was developed in Germany in 1937, mainly because Germany required a reliable internal source of opiates. Because it is an acyclic analog of morphine, methadone acts on the same opioid receptors and thus has many of the same effects. Methadone is also used in managing severe chronic pain, owing to its long duration of action, extremely powerful effects, and very low cost. Methadone was introduced into the United States in 1947 by Eli Lilly and Company