Drug driving limits: knowing the law

We all know the laws on drink driving, but it seems we’re not so clear on drug driving. Drug driving doesn’t just involve illegal drugs, but also some prescription drugs over prescribed levels.  

Data from 40 police forces across England and Wales showed almost 25,000 motorists tested positive for drug driving between March 2015 and January 2018.

Daniel Hutson From the Motor team
minute read

Illegal drugs

Even if your driving seems to be okay, you could still be charged if you’re caught with certain levels of illegal drugs in your blood. These levels are very low: anything below them is considered ‘accidental exposure’.

The drugs covered are:

  • benzoylecgonine (metabolite of cocaine)
  • cannabis
  • cocaine
  • heroin
  • ketamine
  • LSD
  • MDMA
  • methylamphetamine
Illegal drugs

Prescription medicines

It’s illegal to drive in England and Wales if legal drugs impair your driving. It’s also illegal if you have over certain limits of some drugs in your blood and you haven’t been prescribed them.

These sedatives and stimulants can impair your ability to drive, so talk to your doctor about whether you should do so.

  • 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, but they must be prescribed, and you must get a doctor’s advice and stick to their recommendations. This includes if they advise you not to drive while you’re taking them. 

Although these laws don’t apply in Scotland and Northern Ireland, you could still be arrested if you’re unfit to drive.

If you do drive while unfit, you could have:

  • slower reaction times
  • impaired co-ordination
  • blurred vision
  • over-confidence
  • loss of concentration
  • increased risk-taking behaviour
  • inappropriate driving
  • inability to judge distances and speeds properly

What happens if I’m stopped for drug driving?

Police can stop drivers and make them do a ‘field impairment assessment’ e.g. walk in a straight line. 

Officers have also been issued with roadside drug testing kits to do immediate spot checks for levels of cannabis or cocaine in the blood. People suspected of having high levels of other substances will have to do more tests at a police station.

What happens if I’m stopped for drug driving?

What are the penalties for drug driving?

Being convicted of a drug driving offence could result in:

  • a minimum one-year driving ban
  • an unlimited fine
  • up to six months in prison
  • a criminal record
  • a conviction notification on your driving licence which will last for 11 years
  • up to 14 years in prison if you cause death by dangerous driving under the influence of drugs

A drug driving conviction could also mean:

  • a significantly higher insurance premium or difficulty finding an insurance provider
  • trouble getting a visa for travelling to countries such as the USA and Australia

Will a drug driving conviction affect my car insurance?

A drug driving conviction will most probably result in a significantly higher insurance premium. If you do have a conviction you must tell your insurance provider immediately. 

If you have a driving ban, it may be a good idea to cancel your insurance, take your car off the road and make a Statutory Off Road Notification (SORN) while the ban lasts.

Once you’re allowed to drive again, you may find it difficult to find cover as many insurance providers refuse to insure those with drug driving convictions. However, there are specialist insurance providers who could provide you with cover. You’ll just need to accept that it’s probably going to cost a lot more than it did before. See our guide to convicted drivers insurance.

You can make a start by comparing car insurance with us. Just gives us details about you, your car, and any convictions.

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