Eighteen per cent of young people admit to having driven after drinking alcohol, with the majority of these saying that they had done this on multiple occasions, a survey suggests.
And 7% say they have driven after taking illegal drugs, with three-quarters of these admitting that it was not a one-off.
The poll of more than 2,600 17- to 25-year-old drivers was carried out by road safety charity Brake as part of Road Safety Week, which runs until Sunday.
It also found that, of the one in fifteen young people who said they had driven after taking illegal drugs, more than 80% admitted driving on a cocktail of alcohol and drugs. Seventy per cent of those admitting drink- or drug-driving were male.
The survey's results also suggest that there is confusion among young drivers over the length of time it takes to sober up after consuming alcohol.
Brake has launched its Not a drop, not a drag campaign to encourage drivers not to touch alcohol or drugs before they get behind the wheel, and has also called on the Government to cut the legal blood alcohol limit from 80 milligrams in 100 millilitres of blood to just 20 milligrams - the limit in some other European countries such as Sweden and Norway.
And there is speculation today that the Scottish Government will next year cut the country's drink-drive limit to 50 milligrams of alcohol in 100 millilitres of blood, bringing it in line with the majority of EU nations.
Brake chief executive Mary Williams OBE warned that a new generation of drivers were causing deaths on the roads - and pointed to another survey which found that 23% of young people allowed themselves to be carried as passengers by drivers they knew to be drink- or drug-driving.
"It's young people and the vulnerable who die, causing immense trauma," she added.
"Among the dead are many young car passengers who were friends or acquaintances with the drink- or drug-driver who killed them, and who unwisely or unwittingly chose to get in with them due to peer pressure or ignorance."
