Following a KM Group campaign the Home Office is today launching a national publicity drive to raise awareness of the dangers posed by legal highs.

The radio, digital and mobile phone adverts are aimed at people aged 15 to 21 and warn them about the risks of taking the drugs.

Kent has more shops selling legal highs than any other county in the UK, and only Greater London has a higher number, according to research by the Angelus Foundation.

The charity, which aims to raise awareness about legal highs, says the county has 13 head shops - which specialise in selling legal alternatives to drugs such as cocaine and ecstasy.

The Home Office campaign focuses on the risks posed by a range of legal highs including nitrous oxide, which is commonly known as “laughing gas”.

In 2013/14, nitrous oxide was the second most popular drug among young adults, more widely used than powder cocaine, ecstasy and amphetamines.

The campaign directs young people to the FRANK website for help, information or advice about drugs.

Crime Prevention Minister Norman Baker said: “Some of these substances are proven to be more dangerous than illegal drugs and it is vital that young people are informed about the risks associated with their use.

“This summer’s Home Office campaign is part of a wide range of action taken by the government to clamp down on so-called ‘legal’ highs, including banning more than 350 substances.

“We will shortly be announcing the outcome of a review of the UK’s approach to new psychoactive substances.”

A second phase of the campaign later this year will target youth and social workers and others to challenge drug taking behaviour among young people.