Drug Driving Laws in the UK | What Are the Limits?

15th Jun 2023

By Ellie Brown

Drug driving laws in the UK

When thinking of 'driving under the influence', the use of alcohol and illegal drugs on the road may come to mind. However, numerous legal and widely-used medications can also have a negative effect on your driving ability.

But can the use of legal medication when driving be as dangerous as illegal drug driving? The simple answer is yes, and it's crucial to understand the drugs you're taking, as well as the effects they can have on your body, before getting behind the wheel.

Read our drug driving guide to discover the UK's laws and limits for the use of legal and illegal drugs when driving, and the various consequences driving under the influence has.

What are the limits for drug driving in the UK?

Woman Blowing Nose In Car


Research shows that around 47 percent of the UK population takes prescription medication, and despite the rise in awareness, over 50 percent of drivers don't know about the law and how it could affect them.

So, what drugs can you take before getting behind the wheel? And what are the limits to those drugs?

The GOV UK drug driving law passed in 2015 means it's illegal to drive with certain drugs in the body above specified limits. The document details the limits for eight illegal drugs and nine prescription drugs.

Don't underestimate the danger of legal medications. Many ingredients found in common painkillers such as Codeine can cause drowsiness and dizzy spells. It's important to check for these ingredients, and if you're legally prescribed drugs by your doctor, make sure to only take the recommended dosage.

Drug driving limits for illegal drugs

Effects Of Drug Driving


Now onto the more straight forward side of proceedings: illegal substances. The simple fact is that recreational drugs are illegal, so any amount found in your system will land you in trouble with the authorities.

There is zero-tolerance for drug driving, and the limits for illegal drugs are extremely low, so even trace amounts can be detected for offenders to be prosecuted.

Both legal and illegal drugs can have negative effects on your driving ability, including:

  • Slow reaction times
  • Reduced concentration
  • A distorted judgement on time and distance

What are the penalties for drug driving?

Police Pulling Car Over


Every year, thousands of motorists are convicted for drug driving offences including being in possession of drugs, attempting to drive under the influence, or causing death after exceeding the legal drug limit.

There are a number of penalties you'll receive if you’re convicted of driving under the influence of drugs. You can expect:

  • A driving ban for at least a year
  • A criminal record
  • An unlimited fine
  • Possible jail time (up to six months)
  • An endorsement on your driving licence for 11 years (meaning higher insurance costs once you're cleared to drive again)

If you're caught and suspected of drug driving, you'll be tested using ‘drugalyser’ testing kits, which can test immediately for common drugs such as cannabis, cocaine, and a variety of other drugs.

Am I fit to drive?



There are a few actions you can take to ensure you're keeping yourself and other road-users safe when taking medication.

  • Always read the label: Don't be tempted to go over the suggested dosage. If your medication is prescribed by a doctor, always take the recommended amount.
  • Don't look for loopholes: There's no excuse for driving over the drug limit. Put yours and everyone else's safety first, and don't get behind the wheel if you know you shouldn't.
  • If in doubt, don't drive: Simply, if you're not 100 percent sure you're in fit condition to drive, don't risk it. Getting from A to B isn't worth putting yourself and others in danger.

Staying safe on the road

As mentioned previously, there are plenty of penalties for driving under the influence, but nothing comes close to the consequences of putting yourself and other motorists in danger.

Our interactive guide on the effects of drug driving highlights the effects of different drugs and how they can impact a user's ability to drive.