It’s illegal to drive if either:
- you’re unfit to do so because you’re on legal or illegal drugs
- you have certain levels of illegal drugs in your blood (even if they haven’t affected your driving)
Legal drugs are prescription or over-the-counter medicines. If you’re taking them and not sure if you should drive, talk to your doctor, pharmacist or healthcare professional.
The police can stop you and make you do a ‘field impairment assessment’ if they think you’re on drugs. This is a series of tests, eg asking you to walk in a straight line. They can also use a roadside drug kit to screen for cannabis and cocaine.
If they think you’re unfit to drive because of taking drugs, you’ll be arrested and will have to take a blood or urine test at a police station.
You could be charged with a crime if the test shows you’ve taken drugs.
It’s illegal in England and Wales to drive with legal drugs in your body if it impairs your driving.
It’s an offence to drive if you have over the specified limits of certain drugs in your blood and you haven’t been prescribed them.
Talk to your doctor about whether you should drive if you’ve been prescribed any of the following drugs:
- morphine or opiate and opioid-based drugs
You can drive after taking these drugs if:
- you’ve been prescribed them and followed advice on how to take them by a healthcare professional
- they aren’t causing you to be unfit to drive even if you’re above the specified limits
You could be prosecuted if you drive with certain levels of these drugs in your body and you haven’t been prescribed them.
The law doesn’t cover Northern Ireland and Scotland but you could still be arrested if you’re unfit to drive.
View our Drug Driving Leaflet for further information.