8 Things to Know About Benzoylecgonine and Driving After a Blood Test in 2026

Published by Drug Driving Solicitors, specialist defence lawyers for drug driving charges across England and Wales

Your blood test result mentions benzoylecgonine. What does that mean? In most situations like this, you are probably facing a drug-driving allegation. The body creates benzoylecgonine while breaking down cocaine, and too much of it in a driver's blood amounts to a criminal offence in England and Wales, even if that driver felt completely fine.

The guide below explains what benzoylecgonine is, the legal limit, how the police test for it, the penalties you could face and the steps you can take next.

1. What is benzoylecgonine, and how is it formed?

Benzoylecgonine (BZE) forms as your body breaks cocaine down, and this chemical is the main metabolite of cocaine. Taken on its own, it has no intoxicating effect. Its presence in your blood nonetheless counts as strong evidence that cocaine has been used.

It is because BZE is so closely linked to cocaine that police test for it in drug-driving cases. Look for the terms BZE or cocaine metabolite on your paperwork.

2. Why is benzoylecgonine detectable once the effects of cocaine are over?

Benzoylecgonine stays detectable after the effects of cocaine have worn off for one reason: the body clears BZE more slowly than it clears cocaine. Feeling completely sober does not rule out a measurable level.

The time it remains depends on factors such as how much was taken, how frequently it was taken and your individual metabolism. There is, in short, no reliable "safe" waiting time before driving.

3. Is driving an offence if BZE is in your blood?

Yes, where the level exceeds the legal limit. Anyone in England and Wales who drives, or attempts to drive, with a specified drug in their blood above its set limit commits an offence. It came into force on 2 March 2015 and is contained in section 5A of the Road Traffic Act 1988.

The list of drugs covered, and their limits, is in The Drug Driving (Specified Limits) (England and Wales) Regulations 2014. Cocaine and benzoylecgonine are listed separately, which is why either reading can lead to a charge. Separately again, being "in charge" of a vehicle while over the limit is an offence of its own. Sitting in a parked car with the keys is an example. Its penalties differ, and its endorsement is DG40.

4. The level of the benzoylecgonine legal limit

For anyone driving in England and Wales, the benzoylecgonine legal limit is 50 micrograms per litre of blood (µg/L). The limit for cocaine itself is lower, being 10 µg/L.

The government took a zero-tolerance approach to illegal drugs such as cocaine and set limits at a level that rules out accidental exposure. Those limits are not at a level linked to impairment. Laboratories report results as "not less than" a figure, so that measurement uncertainty is allowed for. The limit is therefore never to be treated as a "safe" amount, since any recent cocaine use may put a driver over it.

5. Can you be convicted of drug driving if your driving was not impaired?

Yes. The prosecution, in a section 5A case, only needs to prove that you were driving and that your blood level was above the specified limit. It is not obliged to show that your driving was affected.

The separate offence of driving while unfit through drugs under section 4 of the Road Traffic Act 1988 requires evidence of impairment, which makes it different. Some drivers are investigated for both offences, so check carefully which one you face.

6. How do police test drivers for BZE and cocaine?

The police can conduct a roadside preliminary drug test, screening for cocaine and cannabis with a saliva swab. Even though a positive screen alone cannot convict you, it does allow police to arrest you.

At the police station, a doctor or healthcare professional takes a blood sample, which is sent for laboratory analysis. The law requires that the sample be divided, and a part handed to you for independent testing, as long as you ask for part of it when it is taken. Many drivers are released while they wait for the result, as results can take weeks or even months.

Facing a charge or holding a blood result with BZE? Drug Driving Solicitors can go over your paperwork and explain your options.

7. DG10 drug-driving conviction: penalties to be aware of

The magistrates' court is responsible for hearing these cases. Conviction carries a mandatory disqualification of no less than 12 months, an unlimited fine and up to six months' imprisonment. If you have been convicted of a relevant drink-driving or drug-driving offence in the ten years before this one, the minimum ban will rise to three years.

DG10, the endorsement code, records the conviction on your licence and stays on your driving record for 11 years from the date of conviction. It is also a criminal conviction, so it should not be thought of as just a motoring matter.

Practically, much higher insurance premiums for years are possible. If you drive for work, your employer will be able to see the conviction recorded against your licence.

8. What steps are open to you after a charge?

Specialist advice before your first court hearing is important, because early decisions, including how you plead, can affect the outcome. A solicitor may examine whether the correct procedures were followed, how your blood sample was taken, stored and analysed, and whether the evidence of you driving is sound.

The court can take into account drugs that were consumed unknowingly, for instance through a spiked drink, when deciding the sentence. Where a conviction is likely, the length of the ban above the minimum and the fine may still be influenced by strong mitigation. Every case depends on its own facts, and no particular outcome can ever be guaranteed.

Advice on a benzoylecgonine drug-driving charge when you need it

Benzoylecgonine can stay in your blood after cocaine wears off, and a reading above the limit is enough for a charge whether or not impairment was felt. The penalties are serious, but how your case is prepared may affect what happens.

If you have been charged, or you are waiting on blood test results, get in touch with Drug Driving Solicitors for clear advice on your situation.

This article gives general information about the law in England and Wales; it does not give legal advice. Please seek advice on your own circumstances first.

Frequently asked questions

Can I still use my car before my court hearing?

In most cases, yes. As a ban starts when you are sentenced, being charged does not usually stop you driving. Should the court convict you and delay sentencing, an interim ban can be imposed in the meantime.

Will my drug-driving conviction appear as a criminal record?

Yes. Driving above the specified limit is a criminal offence rather than only an endorsement. The DG10 code also stays on your driving record for 11 years from the date of conviction, and employers who check your licence will see the code.

Can I shorten a drug-driving ban by completing a course?

Not at present. Drug driving has no national equivalent of the drink-drive rehabilitation course, which can shorten some drink-driving bans.

Is prison possible for driving over the BZE limit?

A spell in prison is possible, though uncommon. The Sentencing Council guideline places custody as the starting point only in the most serious category, for example driving commercially or with alcohol or another drug in the blood, combined with poor driving or obvious impairment. Cocaine and BZE found together count as one drug in this context.

Drug Driving Solicitors is a specialist law firm handling drug driving cases across England and Wales. If you have failed a roadside drug test and want to understand your position, call us for a free initial consultation or visit drugdrivingsolicitors.co.uk. Early advice costs nothing, and can make all the difference to the outcome of your case.