Substance Disorders

Understanding Substance Use

“Substance” is a broad term covering numerous types of legal (prescription and non-prescription) and illegal substances. The use of a substance does not imply that the person has a problem. However, prolonged use of a substance, despite negative physical, mental, social, legal or financial consequences, indicates there may be a substance use problem.

Addiction occurs when the 4 Cs are present:


  • Loss of CONTROL
    (of amount or frequency of use)

  • COMPULSION to use

  • Use despite CONSEQUENCES

Contributing Sources: Canadian Mental Health Association, Mental Health First Aid Canada

Learn more on the Centre for Addiction and Mental Health website:

Learn more about specific substances at these links:

Alcohol   |  Amphetamines   |  Caffeine   |  Cocaine and Crack   |  Crystal Meth / Methamphetamines   |  Ecstasy   |  Fentanyl & Prescription Opioids   |  GHB   |  Hallucinogens   |  Hashish   |  Heroin   |  Inhalants   |  Ketamine   |  LSD   |  Marijuana (Cannabis)   |  Methadone   |  Methamphetamines   |  Tobacco

If you, or someone you know, is having trouble with substance use, get help:

If the situation is NOT immediately critical, you have options:

As applicable, contact the person’s psychiatrist, family doctor (who can prescribe medications and make referrals) or your company’s Employee and Family Assistance Program.

Contact the free Ontario Mental Health Helpline for information and referrals to counselling services and supports in your community:


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