Any driver found to have any of the specified drugs above set limits in their blood will be guilty of an offence, whether or not their driving was impaired.
The list includes the following drugs that may be used for medicinal purposes:
- Cannabis (tetrahydrocannabinol, THC)
- Amphetamine (expected to be included later in 2015 once a limit has been agreed)
- Flunitrazepam (no longer licensed in the UK)
The legislation provides a statutory 'medical defence' for patients taking the drugs for medical reasons, who are deemed not guilty of an offence if their driving was not impaired and:
- the medicine was prescribed, supplied, or sold to treat a medical or dental problem, and
- it was taken according to the instructions given by the prescriber or the information provided with the medicine.
Advice for patients
Healthcare professionals should advise patients to:
- continue taking their medicine as prescribed
- read the patient information leaflet for guidance on how the medicine may affect their driving ability
- be aware that it is against the law to drive if their driving ability is impaired
- avoid alcohol as the risk of driving impairment is increased
- not drive if they feel sleepy, dizzy, unable to concentrate or make decisions, or their vision is impaired.
Further information: Drug driving: guidance for healthcare professionals