People from all walks of life have used drugs throughout human history, for many reasons. The most commonly used drugs are alcohol and cannabis. Most substance use does not harm the individual or anyone else. In a small percentage of cases, people can develop problematic use (experience negative consequences from their substance use) or become physically or psychologically dependent on drugs.

This image shows the continuum of substance use. It ranges from no substance use on the far left to full dependence on the far right, with various stages in between.
People do not automatically move along the continuum, and may be at different points on the continuum for different substances. (Ontario HIV & Substance Use Training Program)

Alcohol is a depressant [a] and the most frequently used drug by both adults and youth in Toronto.

  • 77% of adults report drinking alcohol in the past year.[1]
  • 7% of adults report binge drinking on a weekly basis (five or more drinks on one occasion).[1]
  • 29% of students in Grades 7 to 12 in Toronto report having had a drink in the past year.[2]

Cannabis is a depressant and a stimulant [b], and is the most frequently used drug after alcohol.

  • 45% of Ontarians report using cannabis in their lifetime, roughly 4.6 million people.[1]
  • 5% of Torontonians report using cannabis in the past year.[1]
  • 13% of students in Grades 7 to 12 in Toronto report using cannabis in the past year.[2]

Opioids are drugs used medically as pain relievers (e.g. codeine, fentanyl), and also include illegal street drugs such as heroin.

  • 29% of Canadians aged 18 years and older report using opioids in the past five years.[3]
  • 11% of students in Grades 7 to 12 in Toronto reported using prescription opioids for non-medical reasons.2 Most get these drugs from medicine cabinets at home[4].
  • 1% of adults in Ontario report using heroin in their lifetime.[5] However, rates are higher among street-involved adults[6][7] and youth, [5][6] and people with a history of incarceration.[8]

Cocaine, including crack cocaine, is a stimulant drug.

  • 10% of adults in Toronto report using cocaine in their lifetime.[1]
  • 2% of Ontarians report using cocaine in the past year.[1]
  • In Toronto, rates of cocaine use are higher among adults who are homeless and street-involved. [6][7]
  •  One study found 78% reported using crack cocaine in the past year.[7]

[a] Depressants slow the central nervous system and affect parts of the brain that control thinking, behaviour, breathing and heart rate. (Types of Substances, CAMH)

[b] Stimulants increase activity in the central nervous system, including the brain. For example, they speed up mental processes and make people feel more alert and energetic. (Types of Substances, CAMH)

[1] Ialomiteanu, A. R., Hamilton, H. A., Adlaf, E. M., & Mann, R. E. (2016). CAMH Monitor e-Report: Substance Use, Mental Health and Well-Being Among Ontario Adults, 1977–2015 (CAMH Research Document Series No. 45). Toronto, ON: Centre for Addiction and Mental Health.

[2] Toronto Public Health (2015). Healthy Futures: 2014 Toronto Public Health Student Survey, March 2015.

[3] Statistics Canada. (2017) Results of the Survey on Opioid Awareness, November 2017

[4] Boak, A., Hamilton, H.A., Adlaf, E.M., & Mann,. R.E. (2017). Drug use among Ontario students, 1977-2017: Detailed findings from the Ontario Student Drug Use and Health Survey (OSDUHS) (CAMH Research Document Series No. 46). Toronto, ON: Centre for Addiction and Mental Health.

[5] Adlaf EM, Begin P, Sawka E. (2005) Canadian Addiction Survey (CAS): A National Survey of Canadians’ use of Alcohol and Other Drugs: Prevalence of use and Related Harms: Detailed Report. Ottawa, ON: Canadian Centre on Substance Abuse; 2005.

[6] Khandor, E., Mason, K. 2007. The Street Health Report. Toronto, ON.

[7] Health Canada (2014). Monitoring of Alcohol and Drug Use Among High-Risk Populations Study (HRPS). Street-Entrenched Adult Drug Users Prevalence Results 2012-2013.

[8] Kouyoumdjian, F. G., Calzavara, L. M., Kiefer, L., Main, C., & Bondy, S. J. (2014). Drug use prior to incarceration and associated socio-behavioural factors among males in a provincial correctional facility in Ontario, Canada. Canadian Journal of Public Health, 105(3), 198–202.

Rates of Substance Use

Toronto Public Health would like to thank the members of the Public Health Approach to Drug Policy Steering Committee for their assistance in developing this fact sheet.

April 2018