Under the influence

Driving under the influence of alcohol or drugs can have devastating consequences for you and those around you. Learn about your responsibilities as a driver and how to stay safe.

What’s the risk?

According to road safety charity BRAKE!, more than 200 people die each year in the UK in a drink-driving related crash and drug driving being a factor in more than one in 20 fatal crashes in the UK.

Using any kind of substance that can affect your reactions and capability will greatly impact your ability to drive safely, therefore putting you, any passengers you have and other road users at risk.


Even a small amount of alcohol affects your ability to drive. There is no fool-proof way of drinking and staying under the limit, or of knowing how much an individual person can drink and still drive safely.

It is impossible to calculate how much alcohol you have in your blood stream, (even if you know exactly how much alcohol you have consumed), or how long it will stay in your body.

If you’ve been out drinking you may still be affected by alcohol the next day. You may feel OK, but you may still be unfit to drive or over the legal alcohol limit.

Other substances

Illegal drugs and some legal medicines can seriously impact your judgement, reaction time and coordination.

It’s illegal to drive if either:

For a list of the prescription medicines that can affect your driving visit the GOV.UK page. You can also check the instructions that came with your medication as they are likely to mention if you should not drive. You should also always consult your healthcare professional for individual advice on your medications.

Key advice

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