Newsbeat's guide to... legal highs

More legal highs are available in the EU, according to a report by a European drugs agency.

The European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) found 73 new synthetic drugs last year, compared to just 49 in 2011.

The agency says there have been positive changes in the use of more established drugs, such as fewer new users of heroin and declining use of cannabis and cocaine in some countries.

But European officials are worried about man-made drugs being offered on the market.

What are legal highs?

Legal highs are substances which produce the same, or similar effects, to drugs such as cocaine and ecstasy, but are not controlled under the Misuse of Drugs Act.

In many cases, they are designed to mimic class A drugs, but are structurally different enough to avoid being classified as illegal substances, so it is legal to possess and use them.

Why are people worried about legal highs?

There has been little research into the short, medium and long-term effects of legal highs on users.

Some drugs marketed as legal highs have been found to contain some ingredients that are illegal to possess.

It is these reasons that have led to officials like Cecilia Malmström, The European Commissioner for Home Affairs, to voice concern about more new drugs being found.

She thinks that drug policies "need to adapt to changing drug markets".

What are risks?

You increase the risk to yourself if you combine alcohol with any legal or illegal substance that causes a high, including the risk of death.

Because the ingredients are unknown, the NHS says you could have reduced inhibitions, drowsiness, excited or paranoid states, coma, seizures and death.

Why are legal highs legal?

Although possession and use of legal highs is not controlled by the Misuse of Drugs Act it is illegal under medicines' legislation to sell, supply or advertise the substances for "human consumption".

Sellers often refer to them as research chemicals, plant food, bath crystals or pond cleaner to get around the laws.

Earlier this year the government classified legal high black mamba and methoxetamine (mexxy) in the same way as cannabis - as Class B drugs.

How do they get around Europe?

The EMCDDA found that the way the fake legal highs are brought in to the country has changed.

European police agency, Europol, has also suggested that they were now often imported in bulk from China and India rather than being made in secret labs around Europe.

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