Of the 19% who admitted to using drugs while behind the wheel, seven per said they had taken illegal drugs while 12% had used prescription drugs.

Cannabis was the most common illegal drug people admitted to using when driving under the influence (18%), with a further one in ten (10%) admitting to getting behind the wheel having used dangerous class A substances such as cocaine, MDMA and amphetamines.

Worryingly, of those who had been convicted, more than half had been caught twice (56%), and one in five (21%) had offended three times or more.

Young drivers were the worst offenders, with 18-24 year olds the most likely to get behind the wheel when using drugs (25%), according to the study by Confused.com.

Gemma Stanbury, head of car insurance at Confused.com, said: “Drug driving is one of the most serious crimes a driver can commit and one that needs to be addressed to make our roads safer. Road safety should be a top priority and in order to achieve this we need to ensure that the right laws, limits and learning are in place here in the UK.”

The Government last month revealed plans to prosecute people driving under the influence of illegal drugs.

Transport minister Stephen Hammond said: “Drug driving is a menace which devastates families and ruins lives. That is why we are proposing to take a zero tolerance approach with those who drive under the influence of illegal drugs and sending a clear message that this behaviour will not be tolerated.”