People have used alcohol and other drugs throughout human history. Most people do not experience significant health, financial or other harms from their drug use.[1] In a small percentage of cases, people can develop problematic use (experience negative consequences from their substance use) or become physically or psychologically dependent. However, the reasons people develop substance use issues are complex, and include genetic, biological and social factors, including experiences of trauma.

We will always need some laws to address issues such as impaired driving. However, laws that criminalize people simply for using drugs have led to serious health and social harms. For example, people are forced into unsafe spaces and high-risk behaviours leading to increases in overdose, HIV, hepatitis and tuberculosis.[2][3][4]

Experience from around the world finds that making drugs illegal does not stop people from using them.[5] Despite trillions of dollars spent on the “War on Drugs”, the illegal drug market continues to grow and is estimated at between $426 and $652 billion (US) per year.[6] And, people want to use drugs whether they are legal or not. Rates of drug use are more related to cultural, social and economic trends than the strictness of drug laws. For example, after Portugal decriminalized the personal possession of drugs, rates of most drug use did not increase.[5]

Our society often sees drug use, especially the use of illegal drugs, as an individual failing or a lack of self-control. People are seen as “weak” or even “immoral.”[7] The reality is that people use drugs for many reasons, regardless of their legal status. People consume drugs out of curiosity, for pleasure, to enhance social situations, to enhance performance, and also to deal with physical and emotional pain.

Further, while the initial decision to take drugs may be voluntary, long-term, frequent use can lead to problematic use or dependence. Changes in the brain from the use of a particular substance (e.g., opioid) can affect an individual’s ability to control their use of it.[8] In these cases, people may need treatment or other supports. A wide range of treatment options are needed, but are not always available. Further, relapse rates for drug treatment are similar to those for other chronic diseases such as diabetes and asthma.[9] An individual may need to go through several cycles of treatment.

Laws that prohibit the use and possession of cannabis, heroin and other drugs were not based on scientific assessments of harm. They were often based on moral judgements and racist ideas about specific groups of people and the drugs they were using (e.g., Asian immigrants who consumed opium).[10] A study ranking drugs according to the level of harms they produce (e.g., physical, psychological and social) found heroin ranked the highest in terms of individual harm, but alcohol was just as harmful once societal harms were included.[11] In addition, making a drug illegal can increase the harms associated with that drug.[7]  For example, the content and potency of drugs in the illegal market are unknown, and can cause serious harms such as overdose and death. However, in pharmaceutical heroin programs in Switzerland and Vancouver, where the potency and the dose of the drug is matched to the person’s tolerance, there has never been a fatal overdose.[12]

[1] Royal Society for Public Health (2016). Taking a New Line on Drugs. London, UK

[2] Canadian Public Health Association (2014). A New Approach to Managing Illegal Psychoactive Substances in Canada.

[3] Count the Costs. The War on Drugs: Threatening Public Health, Spreading Death and Disease. Retrieved on March 19, 2018 from

[4] Csete, J., Kamarulzaman, A., Kazatchkine, M. et al (2016). The Lancet Commissions: Public health and international drug policy. The Lancet, 387 (10026): 1427-1480.

[5] Transform (2014). Drug decriminalisation in Portugal: setting the record straight.

[6] Global Financial Integrity (2017). Transnational Crime and the Developing World. Washington, DC.

[7] Global Commission on Drug Policy (2017). The World Drug Perception Problem: Countering prejudices about people who use drugs.

[8] Koob, G. F., & Simon, E. J. (2009). The Neurobiology of Addiction: Where We Have Been and Where We Are Going. Journal of Drug Issues, 39(1), 115–132.

[9] National Institute on Drug Abuse (2018). Principles of Drug Addiction Treatment: A Research-Based Guide (Third Edition).

[10] Boyd, S. et al. (2016) More Harm Than Good: Drug Policy in Canada.

[11] Nutt, D., King, L. A., Saulsbury, W., & Blakemore, C. (2007). Development of a rational scale to assess the harm of drugs of potential misuse. The Lancet, 369 (9566), 1047–1053.

[12] Ferri, M., Davoli, M., & Perucci, C. A. (2011). Heroin maintenance for chronic heroin-dependent individuals. Cochrane Database of Systematic Reviews.

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