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Legal highs

Find out about the health risks of legal highs and when to seek medical help.

Drugs information

  • To find out more about specific drugs, including poppers, mephedrone (meow meow), BZP, GBL and naphyrone, go to the A-Z of Drugs on the FRANK website.
  • For confidential advice about all aspects of drugs and drugs use, call the FRANK helpline on 0300 123 6600.

Legal highs are substances used like illegal drugs such as cocaine or cannabis, but not covered by current misuse of drugs laws. This means they are legal to possess or to use.

They are also called club drugs or new psychoactive substances (NPS).

Although these drugs are marketed as legal substances, this doesn’t mean that they are safe or approved for people to use. It just means that they’ve not been declared illegal to use and possess. They are still normally considered illegal to sell under medicines legislation.

Some drugs marketed as legal highs actually contain ingredients that are illegal to possess.

The risks of legal highs

Legal highs can carry serious health risks. The chemicals they contain have in most cases never been used in drugs for human consumption before. This means they haven't been tested to show that they are safe. Users can never be certain what they are taking and what the effects might be.

Other risks:

  • You increase the risk to yourself if you combine alcohol with any legal or illegal substance that causes a high.
  • Effects of legal highs can include reduced inhibitions, drowsiness, excited or paranoid states, coma, seizures and, in a few cases, death.
  • Because the chemical ingredients in a branded product can be changed without you knowing, the risks are unpredictable.
  • Even drugs that look similar or have similar names may be of varying strengths and have different effects.

When to get medical help

Most problems with short-term use of legal highs will settle after you stop taking them. However, the negative effects of some legal highs can take a few days to wear off completely, just like the comedown from stimulants such as cocaine or amphetamines.

If you think you are having a serious negative reaction soon after taking a legal high or you experience problems that do not settle with a little time out, fluids and fresh air, get medical help straight away by going to the accident and emergency (A&E) department of your nearest hospital.

If you are worried about continuing health problems after you've stopped taking the drugs, visit your GP.

But if you think further advice would be helpful before deciding whether to visit your GP, call the FRANK drugs helpline on 0300 123 6600, or NHS 111.

Legal highs and the law

Many drugs that were previously sold as legal highs are now controlled under the Misuse of Drugs Act, including mephedrone (meow meow/mcat), naphyrone, BZP and GBL. This means that they are illegal to possess or to supply to others. There are lots of different types of synthetic cannabinoids and a large number have become Class B drugs.

To find out more about the latest news on legal highs, go to the FRANK website.


Page last reviewed: 09/10/2014

Next review due: 09/10/2016


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The 3 comments posted are personal views. Any information they give has not been checked and may not be accurate.

tuannhutran said on 13 June 2015

Until the system of beaurachracy stops, there's going to be more of these so-called "Legal Highs" drugs bombard the market killing the brains.

What is there to say that the government cannot stop when they license the drugs to legally run the market. The Advisory Council of Misuse Drugs show no responsibilities as far as one is concerned. Total waste of hard earned tax payers.

I call it the work of the devils hand and show no morals to innocent, and vulnerable people, it is inhuman and should stop, this evil drugs has brought not only misery to families causing fatal deaths, and damaging addicts livelihoods.

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cazmarshy92 said on 31 December 2013


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Dangerous Dave said on 31 October 2012

It's good to see the NHS putting up pages about legal highs, I think we need to understand that these chemicals are dangerous!

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