In the UK, there is zero tolerance for drug driving. Illegal substances slow your reaction time, reduce your ability to concentrate and can greatly distort your judgement behind the wheel. When we think of drug driving, it’s illegal drugs like cannabis and cocaine that usually spring to mind, however certain prescription drugs and widely used medications can also lead to drug driving offences due to the impact they have on your driving ability.
With this in mind, it’s important to recognise the specified limits set for both illegal drugs and medications.
What are the Drug Driving Limits for Illegal Drugs?
If you are stopped and suspected of drug driving, you’ll be tested at the roadside. If your test results indicate potential controlled drug use then you’ll be arrested and taken to a police station for further tests.
In the UK it’s an offence to drive with any of the following controlled drugs in your blood at the levels specified. As you can see, the levels of illegal drugs are low, but not completely at zero. This is because common scenarios such as accidental exposure through passive smoking are taken into consideration.
| Illegal Drug | Limit |
|---|---|
| 6-monoacetylmorphine (Heroin) | 5 µg/L |
| Benzoylecgonine | 50 µg/L |
| Methylenedioxymethamphetamine (MDMA) | 10 µg/L |
| Cocaine | 10 µg/L |
| Methylamphetamine | 10 µg/L |
| Delta-9-tetrahydrocannabinol (Cannabis) | 2 µg/L |
| Lysergic Acid Diethylamide (LSD) | 1 µg/L |
| Ketamine | 20 µg/L |
What are the Drug Driving Limits for Prescription Drugs?
Despite growing awareness of how medicinal drugs and prescriptions can impact your ability behind the wheel, many UK drivers are unaware of how drug driving limits and laws affect them. Below is a list of the legal limits set for prescription medicines.
| Prescription Drugs | Threshold limit (µg/L) (microgrammes per litre of blood) |
|---|---|
| Temazepam | 1,000 µg/L |
| Clonazepam | 50 µg/L |
| Oxazepam | 300 µg/L |
| Diazepam | 550 µg/L |
| Morphine | 80 µg/L |
| Flunitrazepam | 300 µg/L |
| Methadone | 500 µg/L |
| Lorazepam | 100 µg/L |
If you take prescription drugs or over-the-counter medicines it’s important to speak with your healthcare professional. They will tell you whether or not they will impact your ability to drive and if there are specific limits for driving while taking them. If the police stop you, always ensure you have information regarding your prescription medicine to hand so you can present this when needed.
What Are the Penalties for Drug Driving?
Driving whilst above the legal limit for any drug, driving without due care and attention, and causing death by careless driving whilst under the influence of drugs are all serious offences you could be charged with if you’re found to be driving whilst over the specified limits of drugs.
Drivers who are successfully convicted of a drug driving offence also face a variety of penalties. Those convicted of being over the specified limit can expect:
- A criminal record: A drug driving conviction means you’ll have a criminal record, which can affect your employment and career prospects, insurance premiums, and even international travel restrictions to places like the USA.
- Unlimited fine: Depending on the severity of the offence and the decision of the court, you can face an unlimited fine that could have serious financial consequences for you going forward.
- Prison term: If convicted you could be facing a prison term of up to 6 months.
- Driving ban: A drug driving conviction can mean the loss of your driving licence, within a minimum 1-year term for a first offence. If this is a repeat offence or there are other factors (such as a crash) then a longer ban could be imposed.
FAQs
Can I drive if I’m taking prescription medicine?
Yes. As long as your prescription medication doesn’t impair your ability to drive and you are within the specified limits set for the drug. If you are unsure how your medicine impacts your driving ability, then speak with your healthcare professional for clarity.
How do I know if my prescription medicine affects my driving?
Controlled drugs will always have leaflets and labels that highlight any potential side effects. If your medicine causes drowsiness or impairs your driving ability then you should speak with your doctor or pharmacist for advice.
How do police test for drugs?
A police officer will use a roadside saliva swab test to detect certain drugs like cannabis and cocaine. If you fail this test, and a specified drug is found to be present then you’ll be taken to the police station for a blood or urine test to determine whether or not you are over drug driving limits.
Can I refuse a roadside drug test?
If you refuse a drug test after being pulled over then you could be charged with “failure to provide a specimen” which carries the same penalties as a drug driving conviction.
