Drug Driving Laws


The legislation now contains sixteen specified drugs - eight illegal and eight medicinal.

Author: David Combes
Reading time: 2 minutes

This article is 6 years old.

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New drug driving laws came into effect on the 2nd March 2016.  They only apply to England and Wales and not to Scotland or Northern Ireland. 

The Road Traffic Act 1988 has been amended to include an offence of driving, attempting to drive or being in charge of a motor vehicle when under the influence of a specified controlled drug exceeding the maximum legal limit for that particular drug.

The legislation now contains sixteen specified drugs – eight illegal and eight medicinal.  This article ONLY deals with the medicinal drugs.

If you have been prescribed any of the following drugs you can still drive even if over the limit, provided your driving is not impaired.  If in doubt you should contact your own doctor.

•    amphetamine, eg dexamphetamine or selegiline
•    clonazepam
•    diazepam
•    flunitrazepam
•    lorazepam
•    methadone
•    morphine or opiate and opioid-based drugs, eg codeine, tramadol or fentanyl
•    oxazepam
•    temazepam

The most worrying feature of these new provisions partly relates to Codeine based drugs that may be purchased over the counter.  Codeine reacts with an enzyme in the liver and converts it to morphine.  Whilst this alone may not be enough to take you over the limit, a cocktail of those with other prescribed drugs might.  As the morphine produced varies with the dosage taken and the body’s own metabolism you should seek advice from your doctor if in doubt.

Whilst there is a defence to the new law where the drugs are legal and being taken for medicinal reasons the same may not apply to your insurance which may be invalidated.

BUT…….. do you really want to risk it?  Check your medication with your doctor or pharmacist if in any doubt at all.

David Combes

In remeberance of David Combes 1948 – 2020

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