The Scottish Executive has teamed up with he Association of Chief Police Officers in Scotland (ACPOS) and the Scottish Road Safety Campaign (SRSC) to raise awareness of the problem - while also pointing out the powers police have to enforce the law.

And the �180,000 campaign has won the backing of the Royal Society for the Prevention of Accidents (RoSPA).

There is little difference between drink-driving and drug-driving

Mike McDonnell RoSPA

The watchdog's Scottish road safety manager, Mike McDonnell, said research had shown that young people were ignorant of the laws covering driving under the influence of drugs.

"After seeing this advert, they will have no excuses," he said.

"It makes it clear that there is little difference between drink-driving and drug-driving - both are socially unacceptable and if you are caught, you face a driving ban and possible prison sentence.

"We hope it will also bring home to young passengers the danger of getting into a car with a driver who has taken drugs. Peer pressure can have a great influence on changing attitudes."

The campaign is targeted mainly at young male drivers.

Those who drive under the influence of drugs are very likely to be caught as the police are well equipped to deal with drug-drivers

Lewis Macdonald Deputy Transport Minister

It will show how impairment tests - such as walking in a straight line and balancing on one leg - are being used by police to catch people driving under the influence of drugs.

Scottish Executive research has suggested that one in 10 people under the age of 40 have driven under the influence of drugs.

Deputy Transport Minister Lewis Macdonald said: "Our concerns about the number of people who use drugs and drive are well founded as too many people are willing to dice with death behind the wheel of their car.

"This executive-funded advert will significantly raise awareness of the risks associated with drug-driving.

"The message will hit home that, besides the very real risks of causing injury to themselves and others, those who drive under the influence of drugs are very likely to be caught as the police are well equipped to deal with drug-drivers."

The launch comes after a weekend crackdown by police which saw 43 drug-drive tests carried out across Scotland.