Substance use and work

With the legalization of recreational cannabis in Canada, questions have been raised about patterns of cannabis use at work, the use of cannabis to treat work-related injuries, and the implications of such uses for work productivity, workplace health and safety and work disability management. IWH research examines these questions, as well as questions about the use and effectiveness of narcotics or opioids to treat pain, including pain associated with work injuries, and patterns of opioid-related harms among workers.

Featured

A bottle of pills spilled on a table.
Research Highlights

Severe pain, not pressure to return to work or lack of accommodation offer, linked to opioid use post-injury

An IWH study found that among a group of injured workers in Ontario, those who experienced severe pain were more likely to use opioids than those who had no or only mild pain.
Published: February 12, 2025
Jars of cannabis on a store display, as seen from outside
Issue Briefing

Cannabis use by workers before and after legalization in Canada

Since 2018, when non-medical use of cannabis was legalized in Canada, a pair of Institute for Work & Health (IWH) studies was conducted to explore the implications of this change for workplaces. This briefing sums up their findings.
Published: December 5, 2024
IWH Speaker Series
IWH Speaker Series

Clearing the haze: Understanding how Canadian workers use and perceive cannabis at work

Recreational cannabis is now legal in Canada and many surveys suggest employers are concerned about the potential implications for workplaces. In this presentation, Dr. Nancy Carnide shares preliminary findings of a survey of workers, conducted in June 2018, aimed at understanding patterns of workplace cannabis use and the social norms and perceptions about such use.
Published: November 2018
A homeless young man sits on the ground, in a tunnel
At Work article

IWH review outlines promising strategies to prevent prescribed opioid abuse

Since the start of the opioid crisis in the late 1990s, communities across North America have tried many different strategies to curb the misuse and abuse of prescription opioids. A new IWH systematic review identifies the most promising ones.
Published: November 2018
Ontario Occupational Health Nurses Association logo
IWH in the media

New systematic review outlines promising strategies to prevent prescribed opioid abuse, overdoses

The opioid epidemic continues to grow unabated across swaths of North America. A new systematic review by the Institute for Work & Health (IWH) now provides a comprehensive assessment of the strategies that have been tried to promote the appropriate use of opioid prescriptions, reduce their misuse and abuse, and prevent overdose deaths.
Published: OOHNA Journal, October 2018
Canadian HR Reporter logo
IWH in the media

Opioids linked to longer disability leaves

A Canadian review of five studies have found a link between opioid prescriptions and longer duration of time on disability, writes Sarah Dobson, who interviews Dr. Nancy Carnide and Dr. Andrea Furlan, among others, about implications of this IWH study.
Published: Canadian HR Reporter, June 2018
The Globe and Mail logo
IWH in the media

High at the helm: Workplaces preparing for cannabis legalization

Virtually nothing is known about why Canadians use cannabis on the job or how common it is for people to consume it at work, says the Institute for Work & Health's Dr. Nancy Carnide in this article on cannabis in the workplace.
Published: The Globe and Mail, April 2018
At Work article

Studies consistent in finding a link between opioids for MSDs and longer work disability

A systematic review on early opioid prescription for MSDs and work disability finds a consistent link with longer work disability. However, review authors urge caution in drawing a conclusion about cause and effect.
Published: February 2018
The Conversation logo
IWH in the media

Marijuana in the workplace: What is unsafe?

The federal government’s commitment to legalize recreational marijuana by July 1, 2018 raises occupational health and safety concerns for many employers. At the Institute for Work & Health (IWH), we have been reviewing the effects of various drugs that act on the central nervous system — including marijuana — on workplace injuries, deaths and near-misses, write IWH's Dr. Andrea Furlan and Dr. Nancy Carnide. What is striking is how little high-quality evidence there is on the impacts of marijuana in the workplace and how inconsistent the existing data is.
Published: The Conversation, January 2018
National Post logo
IWH in the media

Companies fret about hazy rules around pot use

Once recreational cannabis use becomes legal, taking a “smoke break” at work could suddenly become much more complicated, writes Cassandra Szklarski of the Canadian Press. The Institute for Work & Health's Dr. Andrea Furlan and Dr. Nancy Carnide are among those interviewed.
Published: National Post, December 2017