SUMMARY:The response when an employee appears impaired at work should be handled carefully. Information about impairment, services for problematic substance use, and tips for supporting an employee’s effective return to work after being off for treatment are included.

What is impairment at work?

The following information is adapted from Canadian Centre for Occupational Health and Safety.

We often think of impairment as the result of substance use or in terms of addiction or dependence on alcohol or drugs. While not formally defined, the Canadian Human Rights Commission describes the appearance of impairment at work as potentially including the odour of alcohol or drugs, glassy or red eyes, unsteady gait, slurring, or poor coordination.

However, impairment or distraction from focusing on tasks can result from a variety of causes such as work stress, personal or family issues. Some examples include:

  • Medication(s) with side effects such as chemotherapy leading to brain fog, or antibiotics causing nausea
  • Mental or physical fatigue
  • Exhaustion due to long work periods or working more than one job
  • Disruption to sleep patterns
  • Family crisis
  • Responsibility for young children
  • Stressful events including an exam or wedding
  • Traumatic events such as fire or robbery
  • Unresolved conflict
  • Harassment or bullying
  • Exposure to extreme weather; cold can cause lower mental alertness, less dexterity in hands, etc., while heat can result in increased irritability, loss of concentration, loss of ability to do skilled tasks or heavy work, etc.

Process addictions such as gambling, shopping, hoarding, sex, internet use, video gaming, binge eating, etc. may also be a cause of impairment, distraction, or inattention at work.

Workplaces should develop a clear statement of what is considered to be impaired behaviour at work. The Canadian Human Rights Commission uses the following characteristics to describe potential signs of impairment:

  • Personality changes or erratic behaviour (e.g. increased interpersonal conflicts; overreaction to criticism)
  • Appearance of impairment at work (e.g. odour of alcohol or drugs, glassy or red eyes, unsteady gait, slurring, poor coordination)
  • Working in an unsafe manner or involvement in an accident/incident
  • Failing a drug or alcohol test
  • Consistent lateness, absenteeism, or reduced productivity or quality of work

In general, employers should consider if there is a risk to the individual's safety or the safety of others.

Sometimes, there are immediate signs and symptoms present. Other times, it is a pattern of behaviour that may be a concern. The following indicators do not necessarily mean that somebody is impaired or has a substance use problem, however, they may suggest that your employee is in trouble.

Table 1 adapted from Toolkit to Address Problematic Substance Use that Impacts the Workplace available at
Signs and symptoms that could indicate impairment or problematic substance use




  • deterioration in appearance and/or personal hygiene
  • unexplained bruises
  • sweating
  • complaints of headaches
  • tremors
  • diarrhea and vomiting
  • abdominal/muscle cramps
  • restlessness
  • frequent use of breath mints/gum or mouthwash
  • odour of alcohol or drugs on breath or clothes
  • slurred speech
  • unsteady gait

Psychosocial impacts

  • family disharmony (e.g. how the colleagues speak of family members)
  • mood fluctuations (e.g. swinging from being extremely fatigued to ‘perkiness' in a short period of time)
  • inappropriate verbal or emotional response
  • irritability
  • confusion or memory lapses
  • inappropriate responses/behaviours
  • isolation from colleagues
  • lack of focus/concentration and forgetfulness
  • lying and/or providing implausible excuses for behaviour

Workplace performance and professional image

  • calling in sick frequently
  • moving to a position where there is less visibility or supervision
  • arriving late for work, leaving early
  • extended breaks; sometimes without telling colleagues they are leaving
  • forgetfulness
  • errors in judgement
  • deterioration in performance
  • excessive number of incidents/mistakes
  • non-compliance with policies
  • doing enough work to ‘just get by'
  • sloppy, illegible or incorrect work (e.g. writing, reports, etc.)
  • changes in work quality

Responding to employee impairment

While an employee's problematic substance use or addiction may trigger an employer's duty to accommodate, because of potential risk to health and safety, employers may choose to implement strict measures when on-the-job impairment is suspected. This does not relieve the employer of the duty to explore accommodation with the employee.

It is not the role of the supervisor or employer to diagnose a possible substance use or dependency problem. Their role is to identify if an employee is impaired, and to take the appropriate steps as per the organization's policy.

Below are some ideas about responding to potential impairment. Actions taken should comply with any organizational policies or processes that are already in place.

If the impairment is suspected, the employer should determine if the employee has the ability to perform the job or task safely or if there is an impact on cognitive ability or judgement. Each individual should be assessed on a case-by-case basis.

When an employee appears impaired:

  • Immediately escort the employee away from co-workers for a private discussion.
  • Be aware if the employee may be presenting a risk to self or others, and address any safety issues immediately.
  • Request that another person from management or the union join the conversation for safety and to be a witness to the discussion.
  • Objectively state what you have observed. These non-judgmental approaches allow you to check your assumptions before accusing someone of substance use or impairment. For example, rather than saying:
    • "You look drunk," when an employee seems to be exhibiting physical signs of substance use, you could say, "I am noticing that you are responding more slowly than usual, you are slurring your words, and I can smell alcohol or cannabis when I stand beside you."
    • "Did you have a rough night?" when an employee arrives to work late, disheveled and with bloodshot eyes, you could say, "I notice that you were not at your desk when I expected you to be here, and your eyes are red."
  • Provide an opportunity for the employee to explain the behaviour. As noted above, some behaviours that may look like impairment can result from other conditions (e.g. Parkinson's disease, side effects of medication, low blood sugar, concussion, heat stroke, etc.). The employee's explanation should be documented.
  • Call for medical assistance, where appropriate.
  • Contact appropriate workplace stakeholders. This could include a senior manager, human resources professional, or a union representative.
  • Provide safe transportation home.
  • If a decision is made to send the employee home, make arrangements for someone to meet them there. You may wish to call the emergency contact that should be listed in the employee's personnel file. Also, make sure the employee is not driving while impaired. Call a cab or arrange a ride.

When the employee returns to work

  • Respond to co-worker concerns
    • Have conversations with co-workers that allow them to feel heard. Focus on solutions to workplace issues, while respecting the privacy and confidentiality of the employee who is returning.
  • Assess the need for accommodation
  • Clarify consequences for potential relapse or subsequent impairment
    • It is beneficial if the manager and employee have a clear process to follow if the employee's impairment or problematic substance use in the workplace reoccurs. The manager may want to discuss this with the organization's legal counsel, human resources, or senior management.
  • Re-establish a working relationship
    • Once the employee has returned to work, conversations should be supportive and focused on work, and on any performance issues that need to be addressed.
    • Your role is not to deal with problematic substance use, but rather to support the employee to be successful at work.

Adapted in part from: You Are The Key: 10 Steps for Employers to a Drug-Free Workplace.

Helping the employee access information and support

The following resources provide information about problematic substance use, treatment, and assessment.

Canadian Centre on Substance Abuse and Addiction (CCSA)
People can and do recover from addiction to alcohol and other drugs, especially when the right treatments, services and supports are available. Note that CCSA does not provide treatment services.

Addictions Treatment Helplines in Canada
Contact your provincial or territorial helpline for information on available treatment services.

Please note that the information provided here does not address or take into account legal requirements that may apply to your organization and this information should not be relied upon for this purpose.


Impairment and Cannabis in the Workplace
Information provided by the Government of Canada looks at the responsibilities of employers and employees to ensure workplace health and safety.

Cannabis in Canada: Get the facts
Information from the Government of Canada including What you need to know, Cannabis and the border, Cannabis impairment, What industry needs to know and Cannabis in the provinces and territories.