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In every Australian state it is an offence to drive with cannabis, methamphetamine or MDMA in your system, and police can test any driver at the roadside with a saliva test. A prescription for medicinal cannabis does not protect learners or P platers anywhere. Tasmania has a defence for lawfully prescribed and administered drugs. NSW passed a scheme in September 2026 for registered patients, but it only covers unrestricted licence holders. This explainer covers drug testing, medicines and the medicinal cannabis rules in each state as of November 2026.
Key facts
- There are two kinds of offence: driving with a drug present, which needs no proof of impairment, and driving under the influence of any drug, including prescription and over-the-counter medicines.
- Roadside saliva tests look for cannabis (THC), methamphetamine (speed, ice), MDMA (ecstasy) and, in NSW, Queensland and SA, cocaine.
- Refusing a drug test is an offence. The NSW, Victorian, WA and SA handbooks all say so.
- NSW police can also drug test a learner’s supervisor.
How roadside drug testing works
- Police can stop any driver at random and take a saliva (oral fluid) sample. In NSW you wipe a test stick down your tongue.
- If you show signs of being affected by any drug, including a prescription drug, police can do a sobriety assessment and take you to hospital for blood and urine tests (NSW, NT). These cover a wide range of drugs and medicines.
- In WA, a positive roadside drug test, or refusing one, brings a prohibition notice banning you from driving for 24 hours.
| State | Drugs named in the official handbook |
|---|---|
| NSW | Ecstasy, cannabis, cocaine, methamphetamine |
| SA | THC, methylamphetamine, MDMA, cocaine |
| ACT | Cannabis, methamphetamine, ecstasy (2019 handbook; check the current list) |
| VIC | Driving with drugs in your blood or saliva is an offence |
| WA | Prescribed illicit drugs |
| NT | Roadside saliva test, then blood and urine tests that can detect any substance, including some prescription drugs |
| QLD | THC, methylamphetamine, MDMA, cocaine |
| TAS | Ask Transport Services for the current list |
Prescription and over-the-counter medicines
Many prescription and some over-the-counter medicines can make you unfit to drive. It is an offence in every state to drive under the influence of any drug that stops you controlling the car. Before you drive on a new medicine:
- Read the label and the warnings. The NT handbook also says to check for alcohol (ethanol) in the product, which matters if you are on a zero alcohol limit.
- Ask your doctor or pharmacist whether it affects driving.
- Never mix medicines with alcohol.
Medicinal cannabis and driving: state by state
| State | Position as of November 2026 | L and P drivers |
|---|---|---|
| NSW | The Road Transport Amendment (Medical Cannabis and Driving Offences) Bill 2026 passed Parliament in September 2026. Registered patients would not be penalised only because THC is detected, as long as they are not impaired. To register, patients give Transport for NSW evidence of a valid prescription and complete an online education program. Check the start date with Transport for NSW | Excluded: learner, provisional and interlock licence holders cannot use the scheme |
| VIC | A prescription is not a defence to testing positive for THC. Since 1 March 2025, magistrates can decide whether to cancel the licence of a driver who tests positive while using prescribed medicinal cannabis | The presence offence still applies; check with Transport Victoria how the discretion applies to you |
| TAS | Driving with a prescribed illicit drug present is not an offence if the drug was obtained and administered under the Poisons Act 1971. Driving while impaired is still an offence | No L or P exclusion stated, but zero alcohol rules still apply. Check with Transport Tasmania |
| QLD | No medicinal cannabis exception. TMR says there is zero tolerance: any trace of a relevant drug, including THC, can be penalised | Same rule |
| WA | No prescription defence to the THC presence offence. Section 64AC of the Road Traffic Act 1974 makes it an offence to drive with a prescribed illicit drug in your oral fluid or blood, and it contains no defence for prescribed use. A prescription defence exists only for the separate offence of driving while impaired by drugs (section 64AB) | Same rule |
| SA | No prescription defence. Under section 47BA of the Road Traffic Act 1961, the only defence to driving with a prescribed drug present is proving you did not knowingly consume it | Same rule |
| ACT | No prescription defence. Driving with a prescribed drug in your oral fluid or blood is a strict liability offence under section 20 of the Road Transport (Alcohol and Drugs) Act 1977. A bill to add a defence for prescribed medicinal cannabis was introduced in June 2026 and is still before the Legislative Assembly. Check with Access Canberra for any change | Same rule |
| NT | No prescription defence for THC. The Traffic Act 1987 (section 29) gives a medical treatment defence only for some drugs, such as morphine and methadone. THC is listed among the drugs to which that defence does not apply | Same rule |
If you are prescribed medicinal cannabis, talk to your doctor about driving before you get your Ls. You may also need to declare a medical condition. See medical conditions and driving in Australia.
Penalties for learners and P platers
- SA: any drug driving offence disqualifies an L or P driver. Failing to comply with a drug test can mean immediate loss of licence at the roadside.
- WA: a positive roadside test means a 24-hour driving ban, then the offence itself.
- NSW: drug presence brings a fine and loss of licence. Driving under the influence is punished more heavily and can mean prison.
- QLD: a positive roadside test means a 24-hour licence suspension, then a court decides the penalty. From 1 December 2026, new laws double drug driving penalties, with higher fines and longer disqualifications.
- Elsewhere: fines, licence suspension or disqualification. A suspension on Ls or Ps usually extends your time on that stage. See demerit limits for L and P platers.
Common questions
How long does cannabis stay detectable for a roadside test?
No official page gives a safe waiting time, and it varies between people. If you have used cannabis, do not drive.
Can P platers drive on medicinal cannabis in NSW?
No. The NSW scheme only covers unrestricted licence holders. Learner, provisional and interlock licence holders are excluded.
Is there a medical defence in Victoria?
Not to the THC presence offence. Since March 2025, a magistrate can choose not to cancel the licence of a prescribed patient.
Can my supervisor be drug tested?
In NSW, yes. Police can test any driver or supervisor, and can test a supervisor who shows signs of being affected by drugs, including prescription drugs.
Can I refuse a roadside drug test?
No. It is an offence, and in WA it brings the same 24-hour ban as a positive result. In SA it can mean losing your licence at the roadside.
Can cold and flu tablets affect my driving?
Some can. Read the label, and ask a pharmacist if you are unsure.
Related guides
- Zero alcohol for learners and P platers
- Australian road rules explained
- Losing your licence in SA
- Driver fatigue on Australian roads
- Managing risk as a new Victorian driver
Sources
- Transport for NSW, “Road User Handbook”, Drugs and driving (nsw.gov.au)
- NSW Government, “Minns Labor Government’s medicinal cannabis driving reforms pass NSW Parliament” (nsw.gov.au)
- Transport for NSW, “Medical cannabis” (transport.nsw.gov.au)
- Department of Transport and Planning, “Medicinal cannabis and driving laws in Victoria” (transport.vic.gov.au)
- Department of Transport and Planning, “Road to Solo Driving” handbook, Alcohol and drugs (transport.vic.gov.au)
- Tasmanian Government, “Road Safety (Alcohol and Drugs) Act 1970, section 6A” (legislation.tas.gov.au)
- Department of Health Tasmania, “Medicinal cannabis information for patients and the general public” (health.tas.gov.au)
- Western Australian Legislation, “Road Traffic Act 1974”, sections 64AB and 64AC, compilation 14-u0-00 in force from 28 October 2026 (legislation.wa.gov.au)
- South Australian Legislation, “Road Traffic Act 1961”, section 47BA, version 1 January 2026 (legislation.sa.gov.au)
- ACT Legislation Register, “Road Transport (Alcohol and Drugs) Act 1977”, section 20, republication 53, effective 26 November 2025 (legislation.act.gov.au)
- ACT Legislation Register, “Road Transport (Alcohol and Drugs) Amendment Bill 2026”, presented 12 June 2026, status before the Assembly (legislation.act.gov.au)
- Northern Territory Legislation, “Traffic Act 1987”, sections 19A, 28 and 29, as in force at 10 February 2026, and “Traffic Regulations 1999”, regulation 55A and Schedule 1A, as in force at 28 May 2026 (legislation.nt.gov.au)
- Department of Transport and Major Infrastructure WA, “Drive Safe” handbook, Random roadside drug and alcohol testing (transport.wa.gov.au)
- Government of South Australia, “The Driver’s Handbook (MR200, February 2026)”, Alcohol and drugs (mylicence.sa.gov.au)
- Access Canberra, “ACT Road Rules Handbook”, Random breath testing and drug testing (accesscanberra.act.gov.au)
- Northern Territory Government, “Road Users’ Handbook”, Alcohol, drugs and medicines (nt.gov.au)
- Queensland Government, “Drugs and driving”, Department of Transport and Main Roads, last updated 31 August 2026 (qld.gov.au)
- Queensland Government, “New laws passed to crack down on dangerous driving”, joint ministerial statement, 17 September 2026 (statements.qld.gov.au)