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The legal limits for driving under the influence of prescription drugs depends on the drug. Our calculator includes some of the more common prescription drugs. Pick one from the list to find out the legal driving limit.
The penalties for driving under the influence of legal drugs can vary but convictions can result in automatic disqualification from driving for 12 months. After being disqualified from driving, you may find fewer and mainly expensive options when looking for car insurance.
It’s illegal to drive in the UK under the influence of any drug that impairs your ability to drive. The rules apply to both legal and illegal drugs. Even if your ability to drive is unaffected, there is legal limit to the amount of some prescription and non-prescription legal drugs allowed in your system.
It may sound a bit strange for there to be an allowable limit for illegal drugs but there is a low allowable driving limit in case of accidental exposure. For example, for the illegal Class A drug cocaine, it’s 10 micrograms per litre of blood.