A MAJOR public awareness campaign on so-called legal highs is to be launched ahead of a summit to discuss ways to crack down on the sale and supply of the substances in Scotland.

The products have similar effects to drugs such as ecstasy, but fall outwith the UK Government's misuse of drugs laws.

During a debate on the issue at Holyrood, Community Safety Minister Roseanna Cunningham said the growing availability of such substances is presenting a challenge to governments across the world.

Legal highs are often labelled and sold as plant food or bath salts, or marked as not fit for human consumption, as a tactic to avoid the law, the minister said. They are easily accessible online; and have been found to be on sale at petrol stations, newsagents and takeaways, according to research.

The UN and the EU recorded 73 new drugs in 2012, with 693 online shops selling legal highs across Europe in the same period.

Ms Cunningham said the health effects of these new drugs were unknown.

Drug deaths statistics reported in August last year revealed that in Scotland in 2012, there were 37 deaths where new psychoactive substances were implicated. In 32 cases pathologists judged these substances were directly implicated; in five cases they were the only substances implicated.

Ms Cunningham said: "We know they can be harmful with reports of people being admitted to hospital and sometimes tragically dying after reportedly taking them.

"Put simply, regardless of whether a substance is controlled or not, it is impossible to know its content. There are dangers associated with every drug."

She added: "The health implications of new psychoactive substances can be just as serious as controlled drugs, and we have got to challenge the myth that legal equals safe. I wanted this debate to ensure that new drugs are placed firmly on the agenda."

Ms Cunningham said that although banning these substances is a matter reserved to Westminster, a summit will be held to discuss ways to combat the sale and supply in Scotland.

New advice materials will be produced for the Scottish Government's national drugs information service, Know the Score, to help raise public awareness about the dangers of these substances, with Facebook adverts starting today. Research will also be commissioned to help improve the understanding of their impact and use.

Meanwhile, Police Scotland is working with Trading Standards to explore the powers available under civil and criminal law to disrupt supply.

In June last year, the UK Government placed banning orders on four types of the legal high "N-Bomb" and the legal substance "Benzo Fury" after they were linked to deaths.

Labour's Elaine Murray said producers of legal highs were able to replace banned substances with similar alternatives, adding to the challenge of tackling them. She said: "These are not cosy legitimate products which make people feel good - they are pharmaceutical compounds which are being manufactured to bind to receptors in the brain and simulate the effects of illegal drugs. They are as dangerous as those drugs both psychologically and physically."

Tory MSP Alex Johnstone told how in Arbroath such substances were being sold from a shop "just two doors down from a support centre which helps those with addiction issues".

Mr Johnstone added: "These substances are not sold furtively, but sold openly from ordinary retail premises, giving them a facade of respectability and safety."

He said people across Scotland were "rightly protesting at the easy availability of these substances which can do so much harm".