Legislation on legal highs does not go far enough, according to the Local Government Association - it wants a blanket ban on sales of the substances across England and Wales.
Officially described as new psychoactive substances (NPS), they have been linked to a number of deaths.
And recently Spice, a laboratory-created cannabis substitute, was blamed for the admission to hospital of five students at Lancaster University.
What are legal highs?
Legal highs are psychoactive drugs that contain various chemical ingredients, some of which are illegal while others are not. They produce similar effects to illegal drugs like cocaine, cannabis and ecstasy.
How are they sold?
They are sold in a variety of forms - powder, pills, liquids, capsules, perforated tabs and smoking mixtures, to name a few. The substances are often sold in "head shops" alongside drug paraphernalia. There have also been reports of some people injecting legal highs. Because they cannot be labelled as being for human consumption, they are often marketed as plant food, bath salts or incense.
What are their effects?
They are either stimulants (making users feel energised), sedatives (making users feel relaxed or euphoric), or psychedelics (altering perceptions and making users hallucinate).
What are the risks?
The chemicals contained in legal highs have not been tested for safety, so users cannot be sure what the outcome will be. They can cause paranoia, seizures, coma and can also lead to death. The risks can be increased when legal highs are taken with alcohol or with another psychoactive drug. Legal highs can also be addictive and there are additional risks if they are injected.
Drug advisory service Frank says: "Just because a drug is legal to possess, it doesn't mean it's safe."
How much of a problem are they? Research from the Centre for Social Justice (CSJ) showed that there were 97 recorded deaths from legal highs in the UK in 2012, rising from 12 in 2009. The CSJ, an independent think tank, says that the UK has the highest number of legal high users among young people in Europe.
Drug and alcohol treatment charity Addaction says the drugs are often marketed to young people through brightly-coloured packaging but are also becoming the "drug of choice" for other users because they are easy to buy.
A 2014 study by the United Nations Office on Drugs and Crime, which looked at the issue of NPS abuse on a global scale, said: "The use of NPS that poses a health threat has grown rapidly over the past decade and there have been increasing reports of the availability and manufacture of such substances." It added that due to the "fast-paced nature of the NPS market" there was a "continued need for analysis of the scope and magnitude of the global synthetic drugs problem."
What does the law say?
Legal highs are not currently covered by the Misuse of Drugs Act 1971 because drugs are classified as illegal by their chemical compounds. The composition of legal highs is often slightly altered so that the ban is avoided. However, possessing or supplying a legal high is an offence if it contains a banned drug. Drug-driving, including after using a legal high, is illegal.
What is being done?
The LGA wants new legislation, similar to that already introduced in the Irish Republic, to be included in the Queen's Speech at the opening of Parliament. The association says legal highs are a growing problem for councils. In the Irish Republic, it is an offence to advertise, sell, supply, import or export psychoactive substances. Lincoln has already introduced a ban on people taking legal highs in public while other councils, including Newcastle, have used licensing powers or trading standards regulations to restrict sales. Taunton is also banning their use in public places.
The CSJ has also called for police and courts to be given new powers to close "head shops" - adding that there are about 250 of them in the UK. It also wants the government to bring in legislation in line with that introduced in the Irish Republic.
What does the government say?
The Conservative party had previously promised a blanket ban in its manifesto.
BBC/May 22, 2015
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