Medicinal cannabis in the workplace

There’s been a lot of media attention lately about medicinal cannabis and its impact on the roads. But what about its impact in the workplace?

Are you more at risk of having an accident in the workplace if you take medicinal cannabis? Could you face consequences by failing drug testing because of medicinal cannabis? Could you even lose your job?

In this blog, we’ll take a deep dive into the medicinal cannabis issue and in the process hopefully dispel some of the myths and highlight the truths.

What is medicinal cannabis?

In general terms, medicinal cannabis refers to the prescription of cannabis to alleviate the symptoms of various medical conditions, such as epilepsy.

It's crucial to distinguish between medicinal and non-medicinal cannabis. Non-medicinal cannabis is typically used for recreational purposes, primarily to induce a state of euphoria.

According to the Alcohol and Drug Foundation or ADF, medicinal cannabis is for those people who are grappling with chronic or life-threatening ailments, who have found that traditional medications don’t work. Or, in some cases, don’t work as effectively as medicinal cannabis. Additionally, for certain patients, conventional treatments can yield distressing side effects, which medicinal cannabis may help alleviate.

What’s the potential issue with medicinal cannabis, on the roads and in workplaces?

All forms of cannabis can contain the main psychoactive cannabinoid which is called tetrahydrocannabinol (THC). THC acts on specific receptors in the brain and produces the ‘high’.

As well as feeling of euphoria, THC can also produce memory impairment, slower reflexes, increased heart rate, anxiety and paranoia. From a safety perspective, this leaves a person with THC in their system vulnerable. Put simply, they’re more likely to have an accident on the road or in a workplace.

Can you fail drug testing – on the roads or at work – if you are taking medicinal cannabis?

Why can’t they just take THC out of medicinal cannabis?

THC isn’t the only cannabinoid in cannabis, in fact there are around 130.

THC is one of two main cannabinoids that have therapeutic benefits. The other is called cannabidiol (CBD). While some other cannabinoids have been suggested to possess therapeutic properties, there is no proof that this is the case.

While THC is psychoactive it is also widely recognised for its analgesic, anti-inflammatory and antioxidant properties. It also can prevent and alleviate nausea and vomiting.

More research needs to be conducted into CDB and its potential as a medicinal tool. It’s thought to help with conditions such as epilepsy, schizophrenia, and other psychotic disorders. It may even help with type two diabetes, inflammatory bowel disease, specific tumor types and drug dependency.

Medicinal cannabis available in Australia on prescription can come in different combinations. Some may contain only THC or be THC dominant. Some are CBD dominant. At present, there is no product available that is 100% CBD. In other words, there is no product that doesn’t have THC.

What’s the difference between THC and CBD?

The fundamental difference between these two cannabinoids lies in their psychoactive effects.

THC is renowned for its potent psychoactive impact. Conversely, CBD is believed to exert an anti-psychoactive influence, serving to moderate or control the 'high' induced by THC. Additionally, CBD is thought to mitigate several adverse effects that can result from THC consumption, including anxiety.

In total, medicinal cannabis is being used to treat more than 140 medical conditions. Which is why prescriptions of the licit drug are rising.

If medicinal cannabis is legal, why is it an issue on the roads and at work?

While medicinal cannabis is legal if taken with a prescription, this doesn’t lessen the concerns on the roads or in workplaces. Or anywhere else, for that matter, where safety is a concern.

That’s because currently all medicinal cannabis contains THC. And any product that contains THC can leave a person vulnerable to accidents.

This is why, for example, the State Government of Victoria advise people who are taking medicinal cannabis not to drive. They add that unlike alcohol, it’s not known what dose of THC will cause impairment of people.

Alcohol and other drugs – both illicit and licit – when taken with medicinal cannabis can make impairment even more likely. Even medicinal cannabis containing mainly CDB can be a cause for concern when mixed. “While CBD on its own is not known to cause impairment, it may occur if the CBD interacts with other medications.”

In the workplace, the cause is just as real. Particularly if you have a role that is safety-focussed.

As an employer, what can you do to protect your workplace from the risks of medicinal cannabis?

Can you fail workplace drug testing while using medicinal cannabis?

Using medicinal cannabis in the workplace can impact your ability to safely perform your job. And it could result in consequences if you fail workplace drug testing.

If you are taking medicinal cannabis you most definitely can fail workplace drug testing. Whether you do will depend on how much THC is in your system and the testing method.

For the testing method, the key is whether your workplace uses urine testing or saliva testing. With urine samples, THC can be detected for up to one month. With saliva samples, THC can be detected for up to 12 hours after taking medicinal cannabis, although it can be longer for frequent users. This is why saliva testing is the preferred method for Integrity Sampling for all workplace drug testing – because it’s a far more accurate measure of whether a person is safe to be at work.

It’s worth highlighting again that the concern is for safety and the negative effects of THC. Put simply, if you fly a plane, operate heavy machinery, drive a truck, work in a mine or perform any other role where safety is important, having THC in your system puts you – and others around you – at risk.

I’m taking medicinal cannabis. What should I do?

The first advice if you are prescribed medicinal cannabis is to talk to your doctor about the potential negative effects. Ask them if you are safe to drive and safe to go to work.

In the workplace, it’s also a good idea to talk to your employer. It’s not an obligation and you have a right not to divulge your personal information, but if you’re concerned it is best to tell your work. You can then find out about your employer’s policy around prescription medications, the potential impacts on your job and discuss ways to work around the issues.

If you don’t divulge it, you could be opening yourself to consequences if you do fail workplace drug testing down the track. This could potentially include dismissal, particularly if your workplace has zero tolerance for drugs or alcohol.

It’s worth highlighting that in many cases, if you have been prescribed medicinal cannabis, you may need to talk to your employer about your health issues anyway. That’s because for many of the issues where medicinal cannabis is prescribed, there can be an impact on your ability to work, particularly if you have a more manual role.

Medicinal cannabis is just another prescription drug

It’s worth remembering that medicinal cannabis is just another prescription drug. One of many that can leave a person more vulnerable to accidents.

Other drugs that can cause safety issues include sedatives, anti-depressants, antihistamines, stimulants and appetite suppressants, sleeping pills and codeine. This is particularly the case if these medicines are not taken as directed.

Generally, you should always ask your doctor about potential side before medication is prescribed to you. Ask whether you are safe to drive and, if you have a safety-focused role at work, whether there’s an aspect about the drug you should be concerned about. Also, find out about your workplace’s policy around prescription medications.

At the end of the day, we are talking about safety. That’s your safety, the safety of your family and others on the road if you’re driving, the safety of your work colleagues if you’re at work.

It’s in your best interests to stay safe.

Key messages for employers

If you’re an employer, particularly in a workplace where safety is important, you need to be on the front foot when it comes to medicinal cannabis. That doesn’t mean treating it differently but recognising that it’s use is growing and taking steps to ensure your workplace is minimising the risks.

This can include:

  • Reviewing your drug and alcohol policy around medicinal cannabis and prescription drugs.
  • Providing information to your workforce on the risks of coming to work after taking medicinal cannabis or a range of prescription drugs.
  • Undertaking regular, random workplace drug testing to detect people who may come to the work under the influence of THC or other drugs and alcohol.

There’s been a lot of media attention lately about medicinal cannabis and its impact on the roads. But what about its impact in the workplace?


As an employer, what can you do to protect your workplace from the risks of medicinal cannabis?

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