At present in Australia it is illegal to drive with detectable levels of THC in your system. That being said, driving with medical cannabis in Australia can be tricky. Even though it’s legal with a prescription, most states still have strict zero-tolerance laws when it comes to THC in your system. That means you could face penalties if you test positive—even if you’re using it legally under a doctor’s care [12].
Some recent changes in Victoria and Tasmania (as of 2025) now allow limited legal defences for medical cannabis users, but these exceptions are still quite narrow [3]. New laws are slowly being introduced to acknowledge that THC can remain in your system long after its impairing effects wear off. But for now, in Australia, any detectable THC is treated as impairment. Hopefully, this will evolve with time.
What Are the New Laws for Cannabis in Australia?
Medical cannabis is legal in Australia under the Therapeutic Goods Administration (TGA), which allows doctors to prescribe cannabis-based treatments [1].
Recreational cannabis, on the other hand, is still illegal across most of the country. The only exception is the Australian Capital Territory (ACT), where adults can legally possess and grow small amounts for personal use [2].
In 2025, Victoria and Tasmania introduced new laws that give some legal protection to medical cannabis patients who test positive for THC while driving [3]. These changes are a big step, but the rules still come with a lot of fine print.
Has Cannabis Ever Been Legal in Australia?
Cannabis was actually legal in Australia until the 1920s, when it was banned under international drug agreements [4].
Later on, South Australia (in 1987) and the Northern Territory (in 1996) were the first to ease up a bit, introducing decriminalisation. Instead of criminal charges, people caught with small amounts would just get a fine [5].
Medical cannabis became legal in 2016, but using it recreationally is still off-limits in most parts of the country [6].
Is It Legal to Smoke Cannabis in Australia?
If you’re a medical cannabis patient with a prescription, you’re allowed to use it—but smoking it isn’t really recommended. Doctors usually suggest using a vaporizer or taking it as an oil or capsule instead [7].
Recreational cannabis use is only legal in the ACT, and even there, it’s limited. You can possess and grow small amounts for personal use, but selling cannabis is still illegal everywhere in Australia [2].
Drug Driving Laws in Australia
Most Australian states have zero-tolerance rules when it comes to THC and driving. That means even if you’re not impaired, having any detectable THC in your system is still considered an offence [8].
Victoria and Tasmania have recently made changes that let medical cannabis patients present a legal defence in court—but only if they’re not actually impaired at the time of the test [9].
If you’re caught driving with THC in your system, here’s what could happen:
- First offence: You could face a fine of up to $3,500 and lose your licence [10].
- Repeat offences: Expect steeper fines, longer suspensions, and possibly even jail time [11].
Can I Drive With Medical Cannabis?
In most parts of Australia, the answer is no. Even if you have a legal prescription, you can still be penalised if THC shows up in a roadside drug test. There aren’t any broad exemptions for medical cannabis patients [12].
CBD-only medications are generally safe from drug tests, but full-spectrum CBD products might contain small amounts of THC—enough to trigger a positive result [13].
Victoria introduced a law in 2025 that allows patients with a prescription to use a medical defence in court. But even there, if THC is detected, you’ll still be charged initially [3]. The defence just gives you a chance to explain your situation in front of a judge.
Does CBD Show Up in a Roadside Drug Test in Australia?
Nope—CBD isn’t something police test for during roadside saliva tests. Those tests are designed to pick up THC, which is the part of cannabis that causes impairment [14].
That said, if you’re using a full-spectrum CBD product, it might still contain tiny amounts of THC. Even those trace levels could potentially show up on a test and cause issues, so it’s worth checking the label or talking to your doctor to be sure [15].
State-Specific Cannabis Driving Laws
Tasmania (Updated March 2025)
Tasmania has introduced a new law in 2025 that gives some protection to medical cannabis patients—but only if the prescription comes from a Tasmanian-based doctor [16]. If you’re seeing a doctor from interstate, that prescription won’t help you in court.
For non-medical users, the rules are still tough. Penalties include fines, losing your licence, and possibly even jail time [17].
Victoria (Updated March 2025)
In Victoria, medical cannabis patients can now use a legal defence in court if they’re charged after testing positive for THC. The key thing to remember is that you’ll still be charged first, even if you’re not impaired [3].
Unlike before, prescribed patients don’t automatically lose their licence, although driving while impaired is still illegal [18]. Roadside testing remains strict and also checks for MDMA and methamphetamine [19].
New South Wales (NSW)
NSW hasn’t changed its stance—it’s still completely zero-tolerance when it comes to THC. If any is detected in your system, it’s considered an offence [20].
There are no exemptions for medical cannabis patients, and a positive test leads to an automatic 24-hour licence suspension [20]. If it happens again, you could face bigger fines and longer suspensions [11].
Medical Cannabis and Driving in Australia
Legal Considerations
If your prescription includes THC, you need to be extra careful—THC can impair your ability to drive and will definitely show up in a roadside drug test [12]. CBD-only medications, on the other hand, won’t impair you and aren’t picked up by those tests.
Thanks to recent changes in Victoria and Tasmania, some patients now have a legal defence if they’re prescribed medical cannabis and test positive for THC. But that doesn’t mean it’s risk-free—these laws are still evolving, and outcomes can vary case by case [3].
Cannabis Doctors in Tasmania – What You Need to Know
If you’re in Tasmania and using medical cannabis, only prescriptions from Tasmanian-based doctors qualify for the state’s new legal defence when it comes to drug driving charges [16].
That means if you’re seeing a doctor from another state—even through telehealth—the prescription won’t be recognised for legal protection under Tasmania’s current laws [16].
So, if you’re a patient living in Tasmania and you want to drive legally with medical cannabis in your system, make sure your doctor is based locally.
FAQ's
- Can I drive with medical cannabis in Australia?
Generally, no. Most states still treat any amount of THC in your system as illegal when driving—even if you’re a medical cannabis patient. Only Victoria and Tasmania have introduced limited legal defences [3]. - Does CBD show up on a roadside drug test?
No, CBD isn’t tested for. But be careful with full-spectrum CBD products—they might contain small traces of THC, which can trigger a positive result [13]. - How long does THC stay in my system?
It depends on how you use it, but THC can be detected in your saliva for over 24 hours, and it may stay in your blood or urine for weeks—especially with regular use [15]. - What happens if I fail a roadside drug test?
You’ll likely face an immediate 24-hour licence suspension, and depending on the state, you could be fined or required to go to court. Penalties are tougher if you’ve been caught before [20].
TGA, 2016. Medical Cannabis Regulation in Australia. https://www.tga.gov.au/news/blog/introduction-medicinal-cannabis-regulation-australia
ACT Government, 2020. Personal Cannabis Use and Possession Laws. https://www.act.gov.au/__data/assets/pdf_file/0004/2570890/Review-of-the-operation-of-the-Drugs-of-Dependence-Personal-Cannabis-Use-Amendment-Act-2019.pdf
Victoria Parliament, 2025. Drug Driving Law Reforms for Medical Cannabis Patients.
https://www.penington.org.au/victorian-medical-cannabis-drivers-no-longer-face-automatic-ban/
UNODC, 1925. International Drug Treaties and Cannabis Prohibition.
NSW Government, 2025. Road Safety and Drug Testing in NSW. https://www.nsw.gov.au/ministerial-releases/safer-driving-new-years-resolution-nsw-needs-to-lower-road-toll#:~:text=Also%2C%20legislation%20will%20be%20introduced,results%20in%20grievous%20bodily%20harm.
RACGP, 2025. Prescribing Medical Cannabis in Australia. https://www.racgp.org.au/advocacy/position-statements/view-all-position-statements/clinical-and-practice-management/medical-cannabis
National Transport Commission, 2025. Cannabis and Driving: A Legal Review. https://www.ntc.gov.au/sites/default/files/assets/files/Rail%20Standard%20Summary%20of%20Changes%202024.pdf
Tasmania Government, 2025. New Drug Driving Laws for Medical Cannabis Patients.
Queensland Police, 2025. Drug Driving Penalties in Australia. https://www.qld.gov.au/transport/safety/road-safety/drink-driving/drugs
Forensic Toxicology Journal, 2025. THC Detection Windows in Roadside Drug Testing. https://www.mdpi.com/1420-3049/26/11/3291
Victoria Police, 2025. Drug Driving in Victoria: Laws and Penalties.
Australian Road Safety Bureau, 2025. Medical Cannabis and Driving: State-Based Legal Differences. https://www1.racgp.org.au/newsgp/clinical/new-guidance-on-driving-and-medicinal-cannabis
National Drug Research Institute, 2025. THC vs CBD: Driving Safety and Legal Considerations.
https://nida.nih.gov/about-nida/noras-blog/2025/01/new-roadmap-cannabis-cannabis-policy-research
AIHW, 2025. CBD Use in Australia: Implications for Road Safety. https://www.aihw.gov.au/reports/alcohol/alcohol-tobacco-other-drugs-australia/contents/drug-types/cannabis
Youth Law Australia, 2025. Understanding Drug Driving Laws in Tasmania.
Tasmanian Department of Health, 2025. Tasmanian Drug Strategy Implementation Plan 1. https://www.health.tas.gov.au/sites/default/files/2024-12/tasmanian_drug_strategy_implementation_plan_1.pdf
ALRC, 2025. Drug-Impaired Driving and Criminal Law: Implications for Severe Offences.
NSW Supreme Court, 2025. Legal Cases on Drug-Impaired Driving in NSW. https://www.nsw.gov.au/driving-boating-and-transport/demerits-penalties-and-offences/offences/alcohol-and-drug-offences/drink-and-drug-driving-penalties
Roads and Maritime Services NSW, 2025. Fines and Penalties for Drug Driving in NSW. https://www.rezaecolawyers.com.au/traffic-law/offences/drug-driving/#:~:text=The%20law%20in%20NSW%20states,12%20months%20for%20second%20and
Tasmanian Legislation Online, 2025. Road Safety (Alcohol and Drugs) Act 1970. https://www.legislation.tas.gov.au/view/html/inforce/current/act-1970-077