The limit set for each drug is different, and for illegal drugs the limits set are extremely low. They aren't zero to rule out any accidental exposure (for example, from passive smoking).
You should always check with your doctor or pharmacist if you're unsure about whether your prescription or over-the-counter medication will affect your ability to drive.
It’s illegal in England, Scotland 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 have not been prescribed them.
Talk to your doctor about whether you should drive if you’ve been prescribed any of the following drugs:
Amphetamine, for example dexamphetamine or selegiline
Morphine or opiate and opioid-based drugs, for example codeine, tramadol or fentanyl
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 are not causing you to be unfit to drive even if you’re above the specified limits
The legal alcohol limit in England, Wales and Northern Ireland for driving is 80 milligrams of alcohol per 100 millilitres of blood or 35 micrograms of alcohol per 100 millilitres of breath. In Scotland the limit is 50 milligrams of alcohol per 100 millilitres of blood or 22 micrograms of alcohol in 100 millilitres of breath.
There is no way to know how much you can drink and stay under the limit as your weight, age, metabolism, the amount of food you've eaten and other factors can affect this.
It's impossible to get alcohol out of your system quickly, it always takes time and ways of ‘sobering up’ may make you feel better but won’t remove the alcohol from your system.
If you've been out drinking, you may still be affected by alcohol the next day and could lose your licence if you drive and are still over the legal limit.
The only safe option is to avoid alcohol completely if you’re driving as even ‘just one drink’ could put you over the limit.
If you’re driving, don’t drink any alcohol at all.
Testing for alcohol and drug use
The police can stop you at any time and ask you to take a breath test (‘breathalyse’ you) if:
they think you’ve been drinking
You’ve committed a traffic offence
You’ve been involved in a road traffic collision
If you refuse to take a breath test, or fail to supply a sample of breath and don't have a ‘reasonable excuse’, you can be arrested. A reasonable excuse could be a genuine physical or mental condition stopping you from giving a sample; in this case you may be required to have a blood test.
The breath test gives a result straight away. If it shows you’re not over the drink drive limit, you may be allowed to go.
If you fail the breath test, you’ll be taken to a police station and given a final breath test. If it’s positive, you'll be charged.
The police can stop you and conduct a roadside screening test or a field impairment test, both of which may result in your arrest if:
They think you have taken drugs
You’ve committed a traffic offence
You’ve been involved in a road traffic collision
Officers can test for cannabis and cocaine at the roadside, and screen for other drugs – including ecstasy, LSD, ketamine and heroin – at a police station.
Even if you pass the roadside check you may still be arrested if the police suspect that your driving is impaired by drugs and you can be taken to a police station for further tests.
If you're found to be over the drink-drive limit, and/or driving while impaired by drugs, you can receive:
A criminal record
A maximum penalty of six months in prison
An unlimited fine
An automatic driving ban of at least one year (three years if you have been convicted twice in 10 years)
Other problems you may face include:
An endorsement on your driving licence for 11 years
An increased insurance premium
If you drive for work, your employer will see your conviction on your licence
trouble travelling to countries like the USA
Penalties for causing death whilst driving dangerously under the influence of alcohol or drugs
If a driver kills someone while under the influence of alcohol, they can be charged with causing death by careless driving while under the influence of drink or drugs (Section 3A of the Road Traffic Act 1988 (as amended by the Road Traffic Act 1991, section 3)).
The maximum penalty is 14 years imprisonment if the offence was committed before 28 June 2022. If the offence was committed on or after 28 June 2022, the maximum penalty is life imprisonment.
Risks and physical effects
The biggest risk you take when driving under the influence of alcohol or drugs is the risk of causing a collision.
Driving under the influence of drink or drugs is extremely dangerous and can affect your driving in numerous ways, such as:
Ability to judge speed and distance
Reaction and coordination skills
Blurry or impaired vision
Panic attacks and paranoia
Alcohol and drugs can also create a false confidence which can lead to an increase in risk-taking behaviour, which puts your life and the lives of others in danger.
Mobile phones and other devices
It’s illegal to use a handheld mobile phone while driving a motor vehicle on the roads in the UK.
Even using a hands-free option can incur penalties if your driving is deemed to be dangerous.
The police have the right to stop you if they think you’re distracted and not in control of your vehicle, and you can be prosecuted.
It’s still illegal to use your hand held mobile device if you're:
Stopped at traffic lights
Queuing in traffic
Supervising a learner driver
Driving a car that turns off the engine when you stop moving
Holding and using a device that's offline or in flight mode when driving your car
You can use a hand-held phone when:
You’re safely parked and engine off
You need to call 999 or 112 in an emergency and it’s unsafe or impractical to stop
You're making a contactless payment in a vehicle that is not moving, for example at a drive-through restaurant
You're using the device to park your vehicle remotely
Using your mobile device hands-free - you can use hands-free mobile devices while driving your car as long as you do not hold them at any time during usage. The device must not block your view of the road and traffic ahead.
You can get six penalty points on your licence and a £200 fine if you use a hand-held phone when driving.
If you get six points within two years of passing your test you will lose your licence.
You can get three penalty points if you don’t have a full view of the road and traffic ahead or proper control of the vehicle.
You can also be taken to court where you can:
Be banned from driving or riding
Get a maximum fine of £1,000 (£2,500 if you’re driving a lorry or bus)
Having points on your licence will result in higher insurance costs.
Careless driving and distractions
The offence of driving without due care and attention (careless driving) is committed when your driving falls below the minimum standard expected of a competent and careful driver, and includes driving without reasonable consideration for other road users.
Some examples of careless or inconsiderate driving are:
Overtaking on the inside
Diving too close to another vehicle
Driving through a red light by mistake
Turning into the path of another vehicle
The driver being avoidably distracted by tuning the radio, lighting a cigarette etc
Flashing lights to force other drivers to give way
Misusing lanes to gain advantage over other drivers
Unnecessarily staying in an overtaking lane
Unnecessarily slow driving or braking
Dazzling other drivers with un-dipped headlights
Distractions are also causes of dangerous driving, for example:
Using a hand-held phone or other equipment
Reading, or looking at a map
Talking to and looking at a passenger
Lighting a cigarette, selecting music, tuning the radio
Speed limits are set for a reason and exceeding them is illegal. The minimum penalty for speeding is £100 fine and three points added to your licence.
Receiving 12 or more points within three years may disqualify you from driving.
If you’re a newly qualified driver and receive six points during the first two years after passing your test, your licence will automatically be cancelled (revoked). To get it back you’ll need to apply and pay for a new provisional licence and pass both theory and practical tests again.
If you’re caught by a speed camera:
Within 14 days of your vehicle being caught speeding the registered keeper will be sent a;
Notice of Intended Prosecution
Section 172 notice
They, or in the case of a company vehicle, the company secretary, must return the notice within 28 days telling the police who was driving the vehicle. The matter will be referred to the Magistrates’ Court if you ignore the notice.
As the driver, depending on the speed, once you’ve responded to the notice you’ll be sent;
An option for a speed awareness course
A fixed penalty notice
Or a letter telling you to go to court
If you’re stopped by the police they can:
Give you a verbal warning
Send you a fixed penalty notice
Offer a speed awareness course
Order you to go to court – you’ll receive a letter explaining what to do