Penalties for driving while under the influence of drugs can include jail time and losing your license, which is why understanding the rules is so important.
A warning has been issued reminding drivers that it is illegal to get behind the wheel with certain drugs in your system — even if those medications are legal and prescribed by a doctor.
When driving, you must be fully alert and able to focus, and anything that affects your awareness or reaction time can become dangerous.
Most people know there are restrictions on taking certain medications abroad when flying, but the laws around driving while using drugs appear to be far less understood.
Just as you can face fines or imprisonment for carrying medication that is banned in another country, drivers can also face serious consequences for ignoring laws related to drug use behind the wheel.
Put simply, in England, Scotland, and Wales, it is illegal to drive if ‘legal drugs in your body impair your driving’.
This guidance comes directly from the official UK government website, making it something drivers should pay close attention to.

Here’s what you should know about what is and isn’t permitted.
If you’ve been prescribed any of the following medications, you should speak with your doctor before driving:
amphetamine, for example dexamphetamine or selegiline
clonazepam
diazepam
flunitrazepam
lorazepam
methadone
morphine or opiate and opioid-based drugs, for example codeine, tramadol or fentanyl
oxazepam
temazepam
Still, don’t panic as this of course isn’t a blanket ban and you can still take one of these and drive if you’ve followed the advice on how to take them by a healthcare professional.
Understandably, you have to make sure they’re not causing you to be unfit to drive – even if you’re above the specified limits, in most cases it’s okay as long as it’s not impacting your ability.
On the other hand, if you haven’t been prescribed one of these drugs and you’re found driving with them in your system, this is when you could face serious consequences and be prosecuted