Driving Laws and Prescribed Cannabis: Queensland

Zero tolerance, prescribed or not

Queensland's drug driving laws do not distinguish between illicit cannabis use and lawfully prescribed medicinal cannabis. If a roadside oral fluid test detects THC in your system, you can be charged , full stop. That's the short version, and it matters more than almost anything else I write about in this space.

I've sat across the table from enough policy documents to know that access law and road law are almost never written by the same people, at the same time, with the same goals in mind. Queensland is no exception. The Transport Operations (Road Use Management) Act 1995 (Qld) , TORUM, as it's known in the scheduling and enforcement world , establishes the offence of driving with a relevant drug present in your system. Cannabis metabolites are a listed relevant drug. Prescribed or otherwise.

This creates a real and documented gap. You can hold a valid prescription under the federal framework, obtain your product through the Special Access Scheme or via an Authorised Prescriber, comply with every TGA requirement; and still be at legal risk on a Queensland road if you drive after using your medication.

How Queensland's roadside testing works

Queensland Police Service uses roadside oral fluid testing. The test screens for THC, the principal psychoactive compound in cannabis, if you want to understand the chemistry, our tetrahydrocannabinol entry covers the basics. A positive initial screen is followed by a second confirmatory test, also conducted roadside. If that second test is positive, the sample is sent to a laboratory for analysis.

The key point is that the test detects the presence of THC, not impairment. There's no legal threshold here equivalent to the 0.05 blood alcohol limit. Queensland operates on a pure presence standard for cannabis. Even trace amounts can trigger a positive result.

And here's where the pharmacokinetics get complicated. THC is highly lipophilic, it binds to fatty tissue and can persist in the body long after any subjective effects have passed. The detection window in oral fluid is generally shorter than in urine or blood, but it varies considerably between individuals, product type, frequency of use, and dose. There is no reliable "safe" waiting period that applies universally, and I'd be very careful about any source claiming otherwise.

Does the prescription matter at all?

Legally, in Queensland, a prescription does not provide a defence to a drug driving charge based on drug presence alone. This is the position as of 2025 under the TORUM Act framework.

It may, however, be relevant to how a matter is handled downstream; in sentencing, or in the exercise of prosecutorial discretion, but that's a long way from being a defence, and I wouldn't want anyone banking on it.

The Australian Capital Territory took a different legislative approach when it updated its road transport laws, allowing a medicinal cannabis defence in certain circumstances. Queensland has not followed that path. New South Wales similarly maintains a zero-tolerance framework with no prescribed-cannabis exemption, though individual states are at different stages of policy review. Queensland is worth watching, there have been public consultations and advocacy submissions on this issue; but as of writing, the law hasn't changed.

The upshot: if you hold a Queensland prescription for a product containing THC and you are considering driving, that is a conversation to have with your prescribing doctor and, if you want legal advice, a lawyer. Not with a wellness article.

CBD-only products: a different picture

Not all prescribed cannabis products contain THC. Cannabidiol (CBD) is a separate compound, Schedule 4 (prescription only) for products above a certain concentration, or Schedule 3 (pharmacist-only) at lower concentrations, and it is not a targeted substance in Queensland's roadside oral fluid testing. The current tests screen specifically for THC.

So a patient using a CBD isolate product with no detectable THC would not, in theory, return a positive roadside drug test based on that product alone. But this requires some care. Full-spectrum products contain the full range of cannabinoids, including THC. Broad-spectrum products are processed to reduce or remove THC, but trace amounts may remain. A true isolate formulation, by definition, contains only the isolated compound; in this case CBD, with no other cannabinoids present.

Patients need to be clear on exactly what's in their product, at what concentrations, and, honestly; that means reading the certificate of analysis, not just the label. I'll admit this is an area where patient education materials could do a better job.

The federal framework doesn't override state road law

Australia's medicinal cannabis access pathway operates federally, through the TGA's Poisons Standard, the Special Access Scheme, and the Authorised Prescriber framework. Products must meet Good Manufacturing Practice standards and, where listed, appear on the ARTG. Products containing THC above certain thresholds are Schedule 8 controlled drugs.

None of that federal architecture overrides state and territory road safety law. Road use management in Australia falls under state jurisdiction. The Commonwealth can't simply exempt a prescribed drug from a state's drug driving provisions, and it hasn't tried to. The result is a patchwork where a patient might be perfectly compliant with federal law and still face prosecution under Queensland's TORUM Act.

My view, for what it's worth: this is a real policy problem that warrants legislative attention, not just patient education. The current position places an unfair burden on people who are following the lawful access pathway. But that's a separate argument from the legal reality, and the legal reality is what I'm covering here.

Practical considerations for patients

I want to be measured here, because this is genuinely a conversation for prescribers and, where needed, legal practitioners, not a list of workarounds.

A few things worth knowing:

• Queensland Police Service may conduct oral fluid testing at random roadside operations or following an accident. Testing is not limited to situations where impairment is suspected.
• A positive confirmatory roadside test typically results in a suspension of your licence pending the lab result.
• If the lab result confirms presence of a relevant drug, the prosecution proceeds under TORUM. Penalties include fines, licence disqualification, and; for repeat offences, potential imprisonment.
• Carrying your prescription does not prevent a charge. It may be relevant later, but it is not a roadside defence.
• Queensland law as of 2025 does not provide a medicinal cannabis exemption to the drug presence offence. Verify any updates directly with the Queensland Department of Transport and Main Roads or a Queensland lawyer, as this is an area of ongoing policy debate.

Last weekend I was out on the bike somewhere between Bungendore and Braidwood, good riding country, vintage map in the pocket; and I got thinking about how much of the work in access law is just closing the gap between what the legislation technically permits and what people can actually do in their daily lives. The driving issue is a clear example. Access exists on paper. The downstream consequences have not been fully resolved. That's the hard yards of reform.

Laws change, check the source

Queensland's drug driving framework is subject to legislative review, and advocacy groups have been active on this issue for several years. The position described above reflects the law as understood at the time of writing. For current and authoritative information, go directly to the Queensland Department of Transport and Main Roads and the Queensland Legislation website. Do not rely on secondary sources, including this one; when making a decision that could affect your licence or your freedom.

Sources

• Transport Operations (Road Use Management) Act 1995, Queensland Legislation
• Medicinal Cannabis Hub, Therapeutic Goods Administration (TGA)
• Drug Driving; Queensland Department of Transport and Main Roads
• Cannabis, Australian Drug Foundation

, Marcus Hale, Regulatory researcher, TGA & access law