Medicinal cannabis in the Australian workplace: what are the rules?

More Australians are being prescribed legal medicinal cannabis, and many of them are still working, driving, parenting and trying to live normal lives. That sets up a really uncomfortable question for a lot of people: “If I start medicinal cannabis, is my job at risk?”

This post walks through how medicinal cannabis interacts with work health and safety law, drug and alcohol policies, drug testing and anti-discrimination rules in Australia. It is general information only, not legal advice. If you are in a complex situation, you should get specific legal advice and talk with your treating doctor.

If you want a separate overview of how treatment works, doses and product types, our medicinal cannabis online page covers that in more depth.

Key takeaways

• Medicinal cannabis is legal in Australia if it is prescribed, but you still must be “fit for work”, especially in safety-critical jobs. Employers have a duty to manage risks from any drug, legal or illegal.[1]

• THC can impair alertness, reaction time and driving, particularly in the hours after a dose. CBD alone does not appear to impair driving, although it can still cause side effects in some people.[2,5–8]

• Workplace drug tests usually look for the presence of THC or its metabolites, not impairment and not whether the product is prescribed or recreational.[6–9]

• Employees often have to disclose medications that “could impair” them in safety-critical roles. In less risky jobs, privacy and anti-discrimination rules mean disclosure is more nuanced and often tied to whether adjustments are needed.[11–13]

• Problems are much less likely if you have a stable treatment plan with an experienced prescriber, understand your workplace policy and have an open, documented conversation about risk and reasonable adjustments where appropriate.

Is medicinal cannabis “legal at work” in Australia?

Legal medicinal cannabis in Australia is prescribed under federal regulations, but most of the day-to-day rules about work, safety and driving live in state and territory law and in your employer’s policies.

A few key points:

• Having a legal prescription means you are allowed to possess and use that product as directed by your doctor. It does not give you a free pass to be impaired at work.

• Work health and safety (WHS) laws say that businesses (PCBUs) must manage risks from drugs and alcohol, including prescription medicines, and that workers must be fit to do their job and not adversely affect the safety of others.[1]

• In practice, employers usually treat THC-containing products the same way they treat other potentially sedating medicines like opioids or benzodiazepines. The focus should be on safety, not stigma.[1,2]

There is no single law that says “you cannot work if you take medicinal cannabis”.

The real questions are:

1. Can you safely perform the inherent requirements of your role?

2. Are you complying with any specific industry rules or workplace policies, for example zero-tolerance policies on drugs for certain high-risk sites?[1]

Work health and safety duties: “fit for work” is the key

Under the model WHS laws and state equivalents, employers (PCBUs) must, so far as reasonably practicable, ensure the health and safety of workers and others. Safe Work Australia explicitly lists drugs and alcohol, including prescribed medicines, as hazards that can affect a person’s ability to work safely.[1]

That translates into a few practical duties:

• Employers / PCBUs must identify tasks where impairment could lead to serious harm, put controls in place and consult with workers about how drugs and alcohol are managed.[1]

• Workers must take reasonable care of their own safety, not come to work under the influence of drugs or alcohol, and follow reasonable safety policies.[1]

For medicinal cannabis, that usually means:

• Looking at how sedating a product is, what time of day it is used and how long after a dose the worker is performing risky tasks

• Treating medicinal cannabis in the same general category as other sedating medicines, rather than as “recreational drugs”, while still recognising that THC has particular effects on psychomotor function and driving[2,6–8]

Good policies tend to focus on impairment and risk, not moral views on cannabis.

How medicinal cannabis can affect alertness and safety

THC, CBD and cognition in real life

THC is the main psychoactive cannabinoid in cannabis. It can cause euphoria, altered perception, slower reaction times and reduced coordination. CBD is not intoxicating and has a different safety profile, although it can still cause side effects like fatigue or diarrhoea.[2]

Clinical reviews suggest that, in patients on stable low-to-moderate doses of medical cannabis, the overall impact on cognitive function is usually small, especially once they are used to their regimen.[3,4] Acute intoxication with higher THC doses, especially smoked or vapourised, is more likely to cause short-term problems with attention, memory, reaction time and complex tasks.[3,5–8](BioMed Central)

One systematic review of 23 studies found that most did not show major cognitive impairment from prescribed cannabis in adults, but some studies did find mild deficits, and long-term use may still negatively affect cognition.[3] Another semi-naturalistic trial in Australian patients on prescribed medical cannabis found minimal acute impact on cognitive performance in people who were stable on their dose, although the authors still cautioned about driving and other safety-sensitive tasks.[4](BioMed Central)

Key practical points:

• THC-containing products can impair attention, reaction time and coordination for several hours after a dose, particularly at higher doses or in people who are new to therapy.[5–8](PubMed)

• CBD-only products do not appear to impair driving performance in controlled studies, although they can still cause sedation for some people.[6,9](Macquarie University Researchers)

• Long-term, stable medical use with low to moderate THC appears to have only small cognitive effects in most adults, but there may still be subtle impacts and long-term heavy use is more problematic.[3,4]

Not all products are equal

Different products have very different risk profiles.

• A high-THC, fast-acting vapourised flower used in the morning is much more likely to cause on-duty impairment than a small night-time oil dose with a modest THC content.

• Many patients use mixed regimens, for example a CBD-dominant oil in the day and a THC-containing product at night, to balance symptom control and function.[2–4]

If you want a deeper dive into the active compounds themselves, our cannabinoids overview explains THC, CBD and the other cannabinoids in plain language.

It is also worth knowing that THC percentage is not the whole story. The so-called “entourage effect” describes how cannabinoids and aromatic compounds called terpenes work together to shape the overall clinical feel of a product. For example, products heavier in sedating terpenes like myrcene or floral linalool can feel more “night-time”, while brighter citrus profiles rich in limonene may feel more daytime compatible, even at the same THC dose.[2] Our article on THC strength and the entourage effect unpacks this in more detail.(Medio Telehealth)

Safety rules and drug tests do not yet take those nuances into account. From a legal and WHS perspective, THC content, timing and your actual level of impairment are still the main issues.

If you are using flower, device technique and temperature also influence how much THC and terpenes you actually inhale. Our piece on terpenes and vaporiser temperature and our step-by-step guide to using a dry herb vaporiser cover the practical side.(Medio Telehealth)

Workplace drug testing and medicinal cannabis

Many Australian workplaces now use some form of drug and alcohol testing, especially in mining, construction, transport, logistics and other safety-critical sectors. Safe Work Australia notes that testing is one legitimate way to manage risk where a worker “could kill or seriously injure themselves or someone else”.[1](Safe Work Australia)

What tests actually measure

Workplace tests usually look for:

• The presence of THC or its metabolites in saliva, urine or sometimes blood

• Concentrations above a laboratory cut-off, not whether you feel impaired

• No distinction between prescribed and recreational sources

Studies on cannabis and driving show that impairment is strongest in the first few hours after THC use, but THC or its metabolites can remain detectable for much longer, particularly in regular users.[5–8](PubMed)

So it is very possible to:

• Feel completely sober at work

• Still return a positive test because you use a THC-containing product most nights

This mismatch between impairment and detection is a big driver of current debate and law reform around both roadside and workplace testing.[6,8–10](PubMed)

How employers are currently responding

There is a growing body of Fair Work Commission cases where employees using prescribed medicinal cannabis have challenged disciplinary action after a positive test. Legal analyses suggest that:[13–16]

• In genuinely safety-critical workplaces with clear, consistently applied zero-tolerance policies, employers have often been allowed to enforce those policies even when the cannabis is prescribed.

• In other cases, where policies were inconsistent or did not properly consider the worker’s medical situation, terminations have been found to be unfair.

The key themes are risk, clarity and consistency. Courts and tribunals tend to look at:

• How safety-sensitive the role is

• Whether the policy was clearly communicated and applied to everyone

• Whether the employer tried to understand the medical context and consider alternatives

If you are looking for more on the mechanics of testing, cut-offs and driving, we cover common questions like “Will I fail a workplace test if I have a prescription?” on our FAQ page.

Disclosure, privacy and “reasonable adjustments”

Do I have to tell my employer?

There is no single rule that says you must list every medication to your employer. In general:

• Your health information is sensitive and protected by privacy and anti-discrimination law.[11,12]

• Employers can lawfully ask for medical information, including medications, where it is genuinely relevant to your ability to perform the inherent requirements of your job safely. For example, driving heavy vehicles, operating plant or carrying firearms.[1,11]

• In many safety-critical jobs, policies explicitly require you to disclose medications that could impair judgement, coordination or alertness. Failure to do so can be a disciplinary issue, even if nothing bad has happened.[13,14](Fair Work Legal)

  
  

If your role has a strong safety component and the policy says you must declare potentially impairing medications, it is usually safer to disclose your prescription in a controlled, confidential way than to hope it does not come up.

In lower-risk, mostly desk-based roles, the balance tips more toward privacy. You may not be required to disclose unless your condition or treatment affects your capacity to do the job or you are asking for adjustments.[11,12](Australian Human Rights Commission)

Disability discrimination and reasonable adjustment

Chronic conditions like persistent pain, epilepsy, inflammatory bowel disease and some mental health conditions can meet the definition of “disability” under Australian law. That means:[11–13]

• It is generally unlawful to treat you less favourably just because you have a disability or because you use a lawful treatment for it, including medicinal cannabis.

• Employers usually have a duty to consider reasonable adjustments, such as modified duties, altered start times, part-time arrangements or temporary removal from certain high-risk tasks, provided this does not create an unjustifiable hardship or unacceptable safety risk.[11–13](Australian Human Rights Commission)

Examples of adjustments a workplace might consider:

• Moving you away from driving or operating mobile plant in the hours immediately after a THC dose

• Allowing split shifts so night-time THC dosing does not run into early morning high-risk work

• Temporarily reallocating some physical or high-risk tasks while treatment is being stabilised

JobAccess and various human rights bodies have detailed guidance on reasonable adjustment that applies across medical conditions, not just cannabis.[11–13]

Practical tips if you use medicinal cannabis and you work

This is not individual medical or legal advice, but as a general framework:

1. Start with a realistic conversation with your doctor

Tell your prescriber exactly what your job involves, including:

• Any driving or use of heavy machinery

• Night shifts, on-call work, emergency response or solo work

• Any existing drug and alcohol policy you know about

A doctor experienced in this area will usually:

• Start low and go slow, particularly with THC[2]

• Try to time THC-containing doses away from your most safety-critical tasks

• Consider day-time CBD-dominant products and night-time THC where possible[2–4]

Our medicinal cannabis online page explains the assessment and approval process. If you are ready to explore whether treatment is appropriate, you can book via our medical cannabis initial consult booking page.

2. Understand your workplace policy

Ask for a copy of your drug and alcohol policy and any procedures related to prescription medicines. Look for:

• Whether you are in a defined “safety-critical” or “zero-tolerance” role

• What it says about disclosing medications that “could impair” you

• How positive tests are handled, including confirmatory testing and medical review

If anything is unclear, consider speaking confidentially with HR, your health and safety representative or your union.

3. Think about timing, dosing and method of use

Impairment risk is usually highest:

• In the first few hours after THC doses, especially smoked or vapourised products

• When doses are being increased

• When other sedating medicines, alcohol, sleep deprivation or health issues are also in the mix[2–8](RACGP)

Practical ideas to discuss with your prescriber might include:

• Shifting THC-containing doses to evenings where possible

• Using slower-onset oils rather than repeated high-THC vaporiser sessions during the day

• Keeping day-time regimens lower in THC, with more CBD where appropriate

If you use flower, our guide to using a dry herb vaporiser and our article on terpenes and vaporiser temperature can help you use devices more consistently.

4. Document and communicate where it makes sense

If you are in a higher-risk role, it is often helpful to:

• Provide a brief medical letter (with your consent) that describes fitness for work, recommended restrictions and timing, rather than listing every detail of your diagnosis

• Keep written notes or email summaries of any conversations with HR or your manager about your medication and adjustments

This can help everyone show that they have taken WHS duties and reasonable adjustment seriously if there is ever a dispute.

5. Do not ignore driving rules

Driving laws sit alongside workplace rules. In most states it is still an offence to drive with any detectable THC in oral fluid or blood, regardless of whether the product is prescribed.[6,8–10](PubMed)

Medical guidance from bodies such as the RACGP and Austroads generally advises:[6,8,10]

• Avoid driving or other safety-critical tasks for several hours after THC doses, especially when starting or changing treatment

• Be aware that you may test positive even when you feel unimpaired

We cover the driving side in more detail in our FAQ.

Practical tips for employers and managers

For employers, medicinal cannabis is mostly an extension of familiar issues around sedating prescription drugs.

Useful starting points include:

• Risk-based policies

  • Focus on the actual risks of the role. A zero-tolerance rule for THC might be justifiable for someone driving heavy vehicles, but not for a purely desk-based role. Consistency across drugs (for example opioids, benzodiazepines and THC) matters here.[1,6,13]

• Clear processes for prescription medicines

  • Spell out when workers must disclose medications, how that information will be handled confidentially and how decisions about fitness for duty and adjustments are made.

• Reasonable adjustments rather than knee-jerk dismissal

  • Human rights guidance and good practice around disability suggest exploring adjustments such as task changes or rostering tweaks where possible, rather than jumping straight to termination.[11–13]

• Use independent medical advice when needed

  • In complex cases, an independent occupational physician can help assess risk and suggest practical controls.[1,13]

• Training

  • Supervisors should understand the difference between recreational use and prescribed treatment, recognise signs of impairment and know how to escalate concerns respectfully.

    
    

Costs, access and keeping treatment sustainable

For many people, the decision about starting or continuing medicinal cannabis is not just clinical or legal. Cost and long-term sustainability matter too.

Our guide to cheap medical cannabis breaks down typical product prices, dose ranges and ways to keep treatment affordable, including options that may fit better for people who need to stay in the workforce. If you are comparing terpene profiles or wanting to understand how compounds like caryophyllene or myrcene might fit into a plan, our terpene deep dives can help you have a more informed conversation with your doctor.

If you are unsure where to start, the medicinal cannabis online overview plus our FAQ are good first ports of call. From there, booking a consult through the medical cannabis initial consult booking page lets you discuss your health, job and personal risk profile with a doctor who understands the nuances.

References

1. Safe Work Australia. Drugs and alcohol. Canberra: Safe Work Australia; 2025.(Safe Work Australia)

2. Arnold JC, Nation T, McGregor IS. A primer on medicinal cannabis safety and potential. Aust J Gen Pract. 2021;50(6).(RACGP)

3. Wieghorst A, Roessler KK, Hendricks O, Andersen TE. The effect of medical cannabis on cognitive functions: a systematic review. Syst Rev. 2022;11(1):210.(BioMed Central)

4. Arkell TR, et al. A semi-naturalistic, open-label trial examining the effect of prescribed medical cannabis on neurocognitive performance. Drugs R D. 2023.(SpringerLink)

5. Arkell TR, Lintzeris N, Kevin RC, et al. Effect of cannabidiol and Δ9-tetrahydrocannabinol on driving performance. JAMA. 2020;324(21):2177-2186.(JAMA Network)

6. Arkell TR, McGregor IS. Medical cannabis and driving. Aust J Gen Pract. 2021;50(6).(RACGP)

7. McCartney D, Arkell TR, Irwin C, et al. Δ9-Tetrahydrocannabinol and driving-related impairment: a systematic review. Neurosci Biobehav Rev. 2021.(PubMed)

8. Pearlson GD, Stevens MC, Chaarani B. Cannabis and driving. Front Psychiatry. 2021;12:689444.(Frontiers)

9. Boicu B, Badowski M, Collins A, et al. Attitudes toward driving after cannabis use: a systematic review. Drug Alcohol Depend. 2024.(PMC)

10. Austroads. Assessing fitness to drive for commercial and private vehicle drivers. Sydney: Austroads; 2022. Section “Impact of medical conditions on driving”.(Austroads)

11. Australian Human Rights Commission. Disability discrimination: your rights. Sydney: AHRC; 2013.(Australian Human Rights Commission)

12. JobAccess. Guidelines on reasonable adjustment. Canberra: Australian Government; 2025.(JobAccess)

13. HWL Ebsworth Lawyers. High stakes: navigating medicinal cannabis in the workplace. 9 Nov 2023.(HWLE Lawyers)

14. OHS Reps. Worker lawfully dismissed for medicinal cannabis use. SafetyNet 730; 11 Sept 2024.(OHS Reps)

15. ABC News. What are the common misconceptions about taking medicinal cannabis in the workplace and losing your job. Law Report; 14 Nov 2024.(abc.net.au)