Why This Matters
Legal Consequences
Driving under the influence of any impairing substance, including medicinal cannabis, is illegal and dangerous. Even if you're legally prescribed medicinal cannabis, you can still test positive and face legal consequences.
Safety First
Understanding how roadside testing works and how long cannabis stays in your system is vital for protecting yourself and others.
What is Roadside Drug Testing?
THC Detection
THC (Delta-9-tetrahydrocannabinol) 3 the psychoactive component of cannabis
Other Substances
Methamphetamine (ice/speed) and MDMA (ecstasy) are also detected
Not Impairment Tests
These tests do not assess impairment, only the presence of specific drugs. For medicinal cannabis patients, this is critical to understand: a positive result can occur even if you're not feeling impaired.
No Legal Defence
There is currently no legal defence for driving with detectable THC, even if prescribed under the Special Access Scheme or as an Authorised Prescriber product.
How Long Can THC Be Detected
| User Type | Saliva Detection Time |
|---|---|
| Occasional Cannabis Use | Up to 12 hours |
| Frequent Cannabis Use | Up to 30 hours |
| Urine Tests (lab only) | Up to 30 days |
Detection windows vary based on your usage, product type, and individual metabolism.
Source: Alcohol & Drug Foundation, 2024
What Should Patients Know
Same Laws Apply
You are still subject to the same drug driving laws as recreational users, even with a prescription.
CBD-Only Products
CBD-only products (containing <2% THC) are not typically detected by roadside saliva tests.
Oral Forms
Oral forms (e.g., gummies, oils) have longer-lasting effects and extended detection windows.
Inhaled Products
Inhaled products (vapes, flower) may peak quickly but are also detected up to 12-30 hours.
How to Stay Safe
Know your formulation
Ask your pharmacist if your medication contains THC
Track your usage
Keep a log of doses, routes, and times
Avoid driving for 24-30 hours after using THC
Allow sufficient time for THC to clear your system
Talk to your doctor or pharmacist
Discuss driving restrictions specific to your treatment
Consider CBD-only alternatives
If daily driving is essential to your lifestyle
Why Awareness Is Essential
Legal Penalties
Fines, court appearances, criminal record
License Suspensions
Loss of driving privileges
Accidents
Risk to yourself and others
While medicinal cannabis is legal under TGA-authorised frameworks, patients must take personal responsibility to avoid legal penalties, license suspensions, or accidents. Roadside tests don't distinguish between medicinal and illicit THC 3 only presence matters.
Heading: Need Help?
Speak to your prescribing doctor or pharmacist
Your healthcare providers are the best source of personalized advice regarding your specific medication and circumstances. National Alcohol and
Other Drugs Hotline
Call 1800 250 015 for confidential advice and support regarding substance use and driving.
Visit your state transport website for detailed information about penalties and regulations related to drug driving.
Drive With Confidence 2 Know Before You Go
Don't let a lack of information put you or others at risk. Bookmark this page and check in before you drive.