Driving and Medical Cannabis

If you’ve been prescribed medical cannabis in the UK, you may wonder: “Am I still allowed to drive?”

The short answer is yes – if you have a legal prescription and are not impaired. However, UK driving laws around cannabis are strict, and it’s important for patients to understand their rights and responsibilities.

At CPGUK (Cannabis Patient Group UK), we help patients navigate this complex area with clear guidance, advocacy, and support.

What the Law Says

Under the Drug Driving Law (2015), cannabis is classified as a controlled drug. Driving with cannabis in your system can lead to prosecution, even if you feel fit to drive.

🔑 Important difference:

  • Illegal cannabis use → criminal offence.
  • Prescribed medical cannabis → legal, provided you’re not impaired.

📖 Read GOV.UK – Drug Driving Law

DVLA and Medical Cannabis

The DVLA (Driver and Vehicle Licensing Agency) does not require automatic disclosure for medical cannabis prescriptions. However, many underlying health conditions (such as epilepsy, MS, or severe pain) do need to be reported.

If your condition affects your ability to drive safely, you must tell the DVLA.

📖 Check DVLA medical conditions list

Safety and Impairment

Even with a prescription, it is illegal to drive while impaired.

THC-containing medicines (like oils, flower, or Sativex®) may cause:

  • Slower reaction times
  • Impaired coordination
  • Difficulty concentrating

CBD-only medicines are less likely to impair driving, but caution is still advised.

✅ CPGUK Safety Tip: Wait at least 4–6 hours after taking THC-containing medication before driving. Always judge your own fitness to drive.

📖 NHS – Medical Cannabis Guidance

If You’re Stopped by Police

Patients may test positive for THC during roadside tests, even when prescribed. Here’s what to do:

  1. Stay calm and cooperative.
  2. Explain you are prescribed medical cannabis.
  3. Show proof of prescription – keep your prescription letter or pharmacy label in the car.
  4. Answer questions honestly – but remember, impairment assessment is up to police.

📖 Police guidance on drug driving – UK

Practical Guidance for Patients

  • Always take your medicine as prescribed.
  • Avoid increasing doses before driving.
  • Keep a copy of your prescription in your vehicle.
  • Do not drive when starting a new medicine or adjusting your dose.
  • If unsure, don’t drive.

FAQ

Can I drive after taking medical cannabis?
Yes, if prescribed and not impaired. Always leave a safe time gap after dosing.

What if I test positive for THC?
Show proof of prescription and explain your condition. You may still be assessed for impairment.

Do I need to tell my insurer?
Yes. You must disclose your prescription to your insurer to avoid invalid cover.

Is CBD-only treatment safe for driving?
Generally yes, as CBD is non-psychoactive, but always assess your fitness to drive.

CPGUK Support

Driving with a medical cannabis prescription is legal in the UK if used responsibly. Still, laws and patient rights can be confusing.

At CPGUK, we:

  • Advocate for patient rights with the DVLA and authorities.
  • Provide clear guidance on driving laws.
  • Support patients facing issues with police, insurers, or regulators.

👉 Need advice about driving and medical cannabis?
Contact CPGUK today – our patient support team is here to help.

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