Sign In

Cannabis & Driving: Guidance for Patients

Guidance for Patients

Prescribed Cannabis Medicines and Driving

As a patient prescribed with a cannabis medicine, you can possess and take your medicine, and continue to drive a motor vehicle so long as:

  • you are not impaired
  • the cannabis medicine has been prescribed to you and this can be evidenced
  • you are following the directions provided by your specialist consultant and the instructions given by the manufacturer or distributor of the medicine

If you can provide sufficient evidence that you meet the criteria above, you have a statutory medical defence. You should not be arrested and have a defence to the offence of driving or being in charge of a motor vehicle with THC over the specified limit of 2μg/L in the blood.

Following the guidance on this page and in the associated leaflet and raising your statutory medical defence if you are stopped on the roadside, will help you to avoid unnecessary blood samples, arrest and potential prosecution.

Provided you follow the patient responsibilities below, you will have a defence to driving or being in charge of a motor vehicle with THC over the specified limit. You should not be arrested or prosecuted. In the unlikely event that you are arrested, please contact Seed our Future Ltd for further advice and support by emailing

Disclaimer: Please note this guidance does not consist legal advice, which should be sought from a solicitor and be patient-specific.

Prescribed Cannabis Medicines and Driving Guidance for Patients

Patient Responsibilities

  • It is an offence to drive whilst impaired by medicines or for any other reason
  • It is the responsibility of all drivers, including patients, to consider whether they believe their driving is, or might be, impaired on any given occasion
  • Do not drive if you are experiencing sleepiness, poor coordination, impaired or slowed thinking, dizziness, or visual problems
  • Do not to drive when the risk of impairment may be temporarily increased, for example, when first starting, or when first increasing or reducing the dose of your medicine
  • Take particular care if you are taking other prescribed or over-the-counter medicines that could impair your driving or interact with your medical cannabis prescription to impair your driving
  • Take particular care if you have a developing medical condition that could increase the risk of the impairing side effects of your prescription (eg. a serious illness with recent marked weight loss)
  • Be aware that alcohol taken in combination with other impairing drugs can substantially increase the risk of accidents
  • The statutory medical defence cannot be used if a patient is impaired
  • You must follow the directions provided to you by your specialist consultant, including dosing instructions, use with other medicines (prescribed and over-the-counter) and impairment.
  • You must also follow any accompanying instructions (so far as consistent with any directions by your specialist consultant) given by the manufacturer or distributor of the medicine.
  • Carry the following, up to date, documentation with you in your vehicle:
    • A physical or digital copy of your most recent prescription
    • Photo ID eg. driver’s licence
    • If possible, a physical or digital letter from your specialist confirming you are their patient
  • If you need to carry your medication with you, it must be in its original packaging, as dispensed by the pharmacist, with the label showing your name

What to do if you are stopped by the police


  • Written by: Seed Our Future and FCBD Consulting.
  • Reviewed by: BCL Solicitors
  • Support from: CIC Members (Standards Working Group)