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.

Prescription medicines

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:

  • amphetamine, eg dexamphetamine or selegiline
  • clonazepam
  • diazepam
  • flunitrazepam
  • lorazepam
  • methadone
  • morphine or opiate and opioid-based drugs, eg codeine, tramadol or fentanyl
  • oxazepam
  • temazepam

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.

Penalties for drug driving

If you’re convicted of drug driving you’ll get:

  • a minimum 1 year driving ban
  • an unlimited fine
  • up to 6 months in prison
  • a criminal record

Your driving licence will also show you’ve been convicted for drug driving. This will last for 11 years.

The penalty for causing death by dangerous driving under the influence of drugs is a prison sentence of up to 14 years.

Other problems you could face

A conviction for drug driving also means:

  • your car insurance costs will increase significantly
  • if you drive for work, your employer will see your conviction on your licence
  • you may have trouble travelling to countries like the USA