Sell your car today Dealers bid to buy your car!

Drug driving in the UK: what is the law?

July 20, 2022 by

UK drug driving laws are strict, and the consequences of breaking them can be both severe and tragic; we explain all

We all know how dangerous drink-driving is, and the same goes for drug driving.

But while it has been several decades since drink driving became both socially unacceptable and policed with roadside breath tests, it has only been in the seven years or so since drug-drive laws were both toughened up, and policed with roadside tests.

How different drugs affect your driving can vary based both on how you react to the drugs, and what they are. If you take an opiate, for example, you may fall asleep behind the wheel. Consume a hallucinogen or stimulant, meanwhile, and your decision-making skills can become wildly unpredictable and unsuitable; all of these scenarios are potentially lethal.

Some of the numbers surrounding drug driving are staggering: one in 20 fatalities on the roads is said to be caused by someone driving under the influence of narcotics, while some police forces have caught twice the number of people for drug-driving than drink driving in a given year.

This article will set out what the laws, punishments and consequences of drug driving are.

What are the drug driving limits?

Strict, in a word. In 2015, the laws surrounding drug driving in England and Wales were toughened up. The changes saw both tougher limits on the amount of drugs that could legally be in your system before you got behind the wheel of a car, and brought in approved roadside testing methods – commonly known as DrugWipe – to detect two of the most frequently abused illegal drugs.

Illegal drugs

The 2015 laws introduced a zero-tolerance limit for eight commonly used illegal drugs, with “limits set at a level where any claims of accidental exposure can be ruled out”.

The limits are as follows:

Drug (all zero-tolerance approach) Threshold limit

microgrammes per litre of blood (µg/L)

Benzoylecgonine 50µg/L
Cocaine 10µg/L
Delta-9-tetrahydrocannabinol (cannabis) 2µg/L
Ketamine 20µg/L
Lysergic acid diethylamide (LSD) 1µg/L
Methylamphetamine (crystal meth) 10µg/L
Methylenedioxymethamphetamine (MDMA) 10µg/L
6-monoacetylmorphine (heroin) 5µg/L

It’s hard enough to judge how many drinks put a person over the drink-drive limit, which is why all recommendations are to not have a single drink if you’re driving – but drink-drive limits are set at 80 milligrams of alcohol per litre of blood.

Yet while a milligram is a thousandth of a gram, the limits for the above drugs are as low as a single microgram per litre of blood, and one microgram is a millionth of a gram – a tiny, tiny amount. It’s clear, therefore, that the only answer is to not ingest any of the above drugs if you plan on driving (we’ll leave aside the fact that illegal drugs are, well, illegal, and a bad idea).

In fact, it may not be enough to simply not take any of the above drugs if you plan on driving the same day – some legal experts say cannabis may be detected 24 hours or more after it has been consumed, while cocaine can stay in your system for three days or more. In the course of researching this article, we came across the case of a man who lost his licence for being over the limit for cocaine three days after he said he took cocaine.

Legal drugs

It’s not just illegal drugs that can make you unfit to drive: many prescription medications have effects or side effects that can adversely affect your driving.

Limits were set for eight commonly abused prescription drugs in the 2015 legislation. The limits for these are higher than those for the illegal drugs covered above, as the Government took a “road safety risk based approach” to these in recognition that they are prescribed for genuine medical conditions.

The limits for these legal drugs are as follows:

Medicinal drugs (risk based approach) Threshold limit

microgrammes per litre of blood (µg/L)

clonazepam 50µg/L
diazepam 550µg/L
flunitrazepam 300µg/L
lorazepam 100µg/L
methadone 500µg/L
morphine 80µg/L
oxazepam 300µg/L
temazepam 1,000µg/L

A separate approach was taken for amphetamines “that balances its legitimate use for medical purposes against its abuse” with the legal limit for this being 250µg/L of blood.
Despite these limits, the Government said, when introducing these laws, that it is “is unable to provide any guidance on what amounts of dosage would equate to being over the specified limits.” This is because there are too many variables, such as a person’s body shape, size and type, that can affect how drugs are processed.

If you take prescription drugs as directed and your driving is not impaired, then you are not breaking the law by driving. It is wise to keep evidence that you have been prescribed the drugs you are taking with you in your car.

If you are in any doubt as to whether you are fit to drive as a result of taking prescription medication, do not drive.


How are drug-driving laws enforced?

If you are stopped by the police and they suspect you are driving under the influence of drugs, you are likely to be given a roadside drug test, commonly known as a DrugWipe (though this is a brand name). This is wiped around your mouth, and can detect cocaine and cannabis.

If you provide a positive sample for either of these drugs you will be arrested and taken to the police station where an evidential blood test will be given. Fail this and you will be charged.

If the police suspect your driving is impaired by drugs that aren’t detectable by the roadside, you can be taken to the police station for evidential blood tests.

What’s the drug driving penalty in the UK?

Drug driving penalties in the UK are strict.

You will automatically be banned from driving for at least one year, or at least three years if convicted twice in 10 years. You will also have a criminal record.

There is also an unlimited fine, plus you can be jailed for up to six months. Your driving licence will also show a drug-driving endorsement for 11 years after the offence.

Once you get your licence back, car insurance will be very expensive. You may also not be able to travel to some countries, such as the USA, while if you need to drive for work your employer will see your conviction.

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

How to report someone for drug driving

If you want to report someone for drug driving, this can be done in a number of ways. Some police forces have dedicated websites to allow you to do this, while others ask you to contact them with the 111 non-emergency number. If you think someone is currently driving under the influence of drink or drugs you should call 999 to report them.

You will be asked to provide the person’s name, address, description, vehicle make and model, registration number, plus potentially their patterns of behaviour (EG where they where they are likely to be seen).

UK drink drive limit FAQs

How do drugs affect driving?

In many, many ways. The precise effects will depend on the drug you have taken, how much of it you have taken, and how your body responds to it, but include impaired vision, how you judge speed and distances, and your alertness. You may also experience hallucinations, nausea, erratic behaviour, panic attacks and paranoia, dizziness, aggression and drowsiness.

Can you drive on prescription drugs?

Yes, as long as your driving is not impaired and you are not over the limits set out above. If you are in any doubt as to whether you are fit to drive, do not do so. Speak to your doctor for further advice.

How do the police test for drug driving?

A roadside test can be issued for cannabis and cocaine; other drugs are screened for at a police station.

How many points do you get for drug driving?

You can get three to 11 points for drug driving.

Do you lose your licence for drug driving?

Yes – there is an automatic ban of at least 12 months.

Looking for an easy way to change your car? Then carwow is the place to go. You can sell your old car for a great price, and get the best deals on a new one. All through our network of trusted dealers and all from the comfort of your home. Tap the button below to get started today.