New psychoactive substances

Also known as

Plant food, NPS, MDAT, Eric 3, Dimethocaine, bath salts, legal highs, benzofury, bounce, charge, chicken powder, dimitri, Dr. Death, drone, frenzy, ivory wave, killer, m-kat, n-bomb, pink ecstasy, rave, sparkle, red mitsubishi, white magic, white pearl, woof-woof, vanilla sky, 5-IT, 7-UP


Stimulants, depressant, and hallucinogens.


A huge variety of new psychoactive substances have become available in the last 25 years, marketed as safer and legal alternatives to illicit drugs whilst mimicking their effects. They are often made in laboratories and sold via the Internet. With a huge number of chemicals currently available (and can potentially be produced) the UK government have brought in changes to the Misuse of Drugs Act in an attempt to classify the chemicals and any derivatives of them.

Suppliers consequently market them labelled as plant food, bath crystals, research chemicals, or pond cleaner in order to disguise their recreational use and get around the drug laws [1].

New psychoactive substances - often incorrectly called legal highs - contain one or more chemical substances which produce similar effects to illegal drugs (like cocaine, cannabis and ecstasy).

Although some of these so-called 'legal highs' have been legal in the past, many are currently illegal. And it's important to realise that when the Psychoactive Substances Act comes into effect in spring 2016, none of these drugs will be legal to produce, supply, or import (even for personal use) for human consumption.

New psychoactive substances might sound like an awkward term, but it's more accurate than legal highs. You'll still hear people talking about legal highs, and since it's a widely understood term, you might still find it used on this site. But they're all illegal when the new law comes into effect.

There's not enough known about many of these drugs to know about their potency, their effects on people, or what happens when they're used with other substances or alcohol. The packaging might describe a list of ingredients but you can't be sure that this is what's inside. So you can't really be sure what you've bought or been given, or what effect it's likely to have on you or your friends. Many NPS are sold under brand names like 'Clockwork Orange', 'Bliss', 'Mary Jane' and some have been linked to poisoning, emergency hospital admissions and, in some cases deaths [2].

New psychoactive substances are sold in different forms such as powders, pills, smoking mixtures, liquids, capsules, or on perforated tabs.

The packaging is usually designed to get your attention using a catchy brand name and bright colours. It might describe a list of ingredients but you can't be sure that this is what's inside.

The powders can range from white to brown to yellow in colour and from flour-like to little crystals in consistency. The pills and capsules vary widely in size, shape and colour.

The smoking mixtures tend to come in colourful packaging, often with labels describing the contents as incense or herbal smoking mixture, and the contents look like dried herbs, vegetable matter or plant cuttings. It's common for synthetic cannabinoids to be added to dried herbs, vegetable matter or plant cuttings to make a smoking mixture.

New psychoactive substances that come as powders, pills or capsules tend to be snorted or swallowed, while smoking mixtures are either smoked in a joint or spliff or by using a pipe.

There have been reports of some people injecting NPS. Injecting any drug is particularly dangerous because a drug is more likely to reach harmful or fatal levels by this route. Also, veins can be damaged by the injecting process and an abscess or blood clot may develop, which can then cause serious health problems like blood infection or heart problems.

Injecting can also lead to serious scarring and can be disabling or even fatal. Sharing injecting equipment such as needles or syringes, runs the additional risks of catching or spreading viruses such as HIV or hepatitis C [2].

NPS are drugs which were designed to replicate the effects of illegal substances like cannabis, cocaine and ecstasy whilst remaining legal - hence their previous name 'legal highs'.

NPS began to appear in the UK drug scene around 2008/09. They fall into four main categories -

  • Synthetic cannabinoids - these drugs mimic cannabis and are traded under such names as Clockwork Orange, Black Mamba, Spice and Exodus Damnation. They bear no relation to the cannabis plant except that the chemicals which are blended into the base plant matter act on the brain in a similar way to cannabis.
  • Stimulant-type drugs - these drugs mimic substances such as amphetamine, cocaine and ecstasy and include BZP, mephedrone, MPDV, NRG-1, Benzo Fury, MDAI, ethylphenidate.
  • Downer'/tranquiliser-type drugs - these drugs mimic tranquiliser or anti-anxiety drugs, in particular from the benzodiazepine family and include Etizolam, Pyrazolam and Flubromazepam.
  • Hallucinogenic drugs - these drugs mimic substances like LSD and include 25i-NBOMe, Bromo-Dragonfly and the more ketamine-like methoxetamine [3].

When you buy new psychoactive substances, you can never be sure that what you are buying is what it is claimed to be. Even if the packaging describes a list of ingredients, you can't be sure that it contains the same substances.

Forensic testing of NPS has shown that they often contain different substances to what the packaging says, or mixtures of different substances. This means that you could end up taking a drug which has stronger or different effects and risks than you expected [2].

Very little controlled research is available for these substances and therefore side effects and possible dangers are not yet fully known. Even if a substance is sold as 'legal' or 'herbal' does not mean that it is safe for consumption. Deaths have been reported as a result of using these substances [1].

What does it look like?

NPS are normally sold as powders, pills or capsules. The powders can range from white to brown to yellow in colour and from flour-like to little crystals in consistency. While the pills and capsules can range in size, shape and colour.

The smoking mixtures tend to come in colourful packaging, often with labels describing the contents as incense or herbal smoking mixture, and the contents look like dried herbs or plant cuttings. Although they look herbal, they are actually plant material sprayed with potent chemicals [4].


Some may be derived from intoxicating plant species; some may be chemicals made in laboratories. Substances may be imported; sold over the internet and in some specialist shops [1].


According to 2016 statistics from the Home Office on drug use in England and Wales in 2015 -

  • The prevalence of NPS use is generally low among adults aged 16 to 59. Fewer than 1 in 100 (0.7%) adults had used an NPS in the last year. This equates to around 244,000 adults.
  • Use of NPS in the last year is concentrated among young adults aged 16 to 24. Around 1 in 40 (2.6%) young adults took an NPS in the last year. This equates to around 162,000 people.
  • Use of NPS in the last year was concentrated among young men.
  • Several lifestyle factors were associated with last year NPS use. These included visits to a pub or a nightclub in the last month, consumption of alcohol in the last month and use of another drug in the last year.
  • Herbal smoking mixtures were the most commonly used NPS.
  • NPS were most commonly obtained from a friend, neighbour or colleague (35%). Other common sources were shops (25%), known dealers (9%) or the Internet (8%) [3].

Why take it?

Sought after effects

  • Varied. Many substances will have stimulant or hallucinogenic effects or a combination of both [1].

Undesired effects

  • Varied. See individual substances for more information, if available [1].

What are the different forms?

Drugs including 'legal highs' that you can become addicted too [2].

  • Stimulant NPS can make you feel overconfident and disinhibited, induce feelings of anxiety, panic, confusion, paranoia, and even cause psychosis, which can lead you to put your own safety at risk. This type of drugs can put a strain on your heart and nervous system. They may give your immune system a battering so you might get more colds, flu and sore throats. You may feel quite low for a while after you've stopped using them.
  • Downers or sedative NPS can reduce inhibitions and concentration, slow down your reactions and make you feel lethargic, forgetful or physically unsteady, placing you at risk of accidents. This type of drugs can also cause unconsciousness, coma and death, particularly when mixed with alcohol and/or with other downer drugs. Some people feel very anxious soon after they stop taking downers, and if a severe withdrawal syndrome develops in heavy drug users, it can be particularly dangerous and may need medical treatment.
  • Psychedelic or hallucinogenic NPS which act like LSD, magic mushrooms, ketamine and methoxetamine can cause confusion, panics and strong hallucinatory reactions ('bad trips'), and their effects can make you behave erratically and put your own safety at serious risk - including from self-harm. This can interfere with your judgement, which could put you at risk of acting carelessly or dangerously, and of hurting yourself, particularly in an unsafe environment.
  • Synthetic cannabinoids could lead to severe or even life-threatening intoxication when taken in sufficiently larger doses. They can also affect your central nervous system, and lead to seizures, fast heart rates, high blood pressure, sweating, increased body temperature, being agitated and being combative (ready to fight) [2].


The main effects of almost all psychoactive drugs, including so-called legal highs, can be described using the four main categories below. While drugs in each of these categories will be similar in the effects they produce, they will have widely different strengths and effects on different people [2].

  • Stimulants (like mephedrone, naphyrone) act like amphetamines, cocaine, or ecstasy, in that they can make you feel energised, physically active, fast-thinking, very chatty and euphoric.
  • Downers or sedatives (like GBH/GBL, methoxetamine) act similarly to benzodiazepines (drugs like diazepam or Valium), or GHB/GBL, in that they can make you feel euphoric, relaxed or sleepy.
  • Hallucinogens or psychedelics (like NBOMe drugs) act like LSD, magic mushrooms, ketamine and methoxetamine. They create altered perceptions and can make you hallucinate (seeing and/or hearing things that aren't there). They can induce feelings of euphoria, warmth, 'enlightenment' and being detached from the world around.
  • Synthetic cannabinoids (like Spice or Black Mamba): act similarly to cannabis. The effects of these are similar cannabis intoxication: relaxation, altered consciousness, disinhibition, a state of being energised and euphoria [2].


You can't really be sure of what's in a 'legal high' that you've bought, or been given, or what effect it's likely to have on you or your friends. For many NPS, there has been little or no research into the risks from human consumption. Will have widely different strengths and effects on different people.

Many of these risks are increased if the drug is combined with alcohol or with another psychoactive drug. There have been cases of death too.

Risks may include -

  • confusion,
  • drowsiness,
  • paranoia,
  • manic behaviour,
  • panic,
  • heart attack,
  • coma,
  • seizures,
  • death [1].

Experimenting with these substances is risky as no-one can be certain what they are taking or how they will react. See individual substances for more information, if available [1].

Are they dangerous?

Little is known about either the short or long-term effects of NPS use. The packets containing the drugs do not necessarily list the ingredients and even branded products can vary in content from batch to batch. So users don't necessarily know what they are taking, what the appropriate dose might be or how their body may react.

Some (e.g. strong synthetic cannabinoids) are thought to be significantly more dangerous than others (e.g. nitrous oxide) in terms of their short- and long-term mental and physical effects, and the risk of addiction. However, there are always risks associated with any form of drug-taking, both from the effect of the drug itself, and the increased risk of accident [5].

Why do people die from them?

People have died from NPS for a variety of reasons: perhaps the drug has contained a toxic substance or someone has misjudged the correct dosage and taken too much. There have been cases where someone thought they were taking one drug but in fact it turned out to be something else. Because the person using the drug may not know what it contains, it will also be harder for emergency services, such as paramedics and doctors, to know how to respond appropriately [5].

Do they have long-term health risks?

Very little is known about either the short- or long-term effects of these drugs. However, it seems likely that some will carry longer-term health risks - for example, experts are concerned that synthetic cannabinoids have the potential to be more harmful than cannabis because of the high strength of these compounds compared to cannabis and because of the range of different chemicals being produced [5].


Can you get addicted

New psychoactive substances that have the same effects as drugs like cannabis, cocaine and amphetamines can potentially get you hooked.

Most stimulant and sedative drugs used recreationally have turned out to be addictive to some degree. So the regular NPS use, particularly drugs with sedative or stimulant effects, could potentially lead to a compulsion to use or even a risk of withdrawal symptoms when you stop using them.

Some people feel very anxious soon after they stop taking downer-type drugs. If a severe downer withdrawal syndrome develops in a heavy drug user, it can be particularly dangerous and the person affected may need medical treatment [2].


Although some of these so-called 'legal highs' were legal in the past, since the Psychoactive Substances Act came into effect on 26 May 2016, none of these drugs are legal to produce, supply or import (even for personal use, e.g. over the internet) for human consumption. This includes selling them or giving them away for free (even to friends) when they are going to be taken to get high.

The 'legal highs' that were made illegal as class A, B or C drugs under the Misuse of Drugs Act, are still covered by that legislation. All other psychoactive substances not currently covered by the Misuse of Drugs Act will fall under the Psychoactive Substances Act [2].

Did you know?

Like drinking and driving, it's illegal to drive if your driving has been impaired by taking drugs. With some drugs, you can even remain unfit to drive the next day. As well as this drug-impaired-driving offence, it's now illegal in England and Wales to drive over set levels for any of 17 named drugs (legal and illegal) in your body, whether or not you are impaired. Very low limits have been set for some common illegal drugs such as cannabis, cocaine and MDMA. You can get a heavy fine, be disqualified from driving or even go to prison. Check out the Think! website for more details [2].


  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Research Chemicals, New / Novel Psychoactive Substances, New & Emerging Drugs, 'Legal Highs, 2014,
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 New psychoactive substances, 2016,
  3. 3.0 3.1 New psychoactive substances, 2016,
  4. Legal highs, 2017,
  5. 5.0 5.1 5.2 FAQs - New Psychoactive Substances, 2016,