This site is intended for health professionals only

Home / OTC / The lowdown on legal highs

The lowdown on legal highs


29 Apr 2009

‘Drug Misuse Declared’ is an annual Statistical Bulletin based on data from the British Crime Survey that tracks illicit drug use in the UK. The 2008/9 Bulletin reports that about a third of 16-59 year olds have ever used illicit drugs, with cannabis being the most commonly used.1 Since 1996, there has been an overall reduction of illicit drug use, but an increase in class A drug use. 16-24 year-olds have the highest illicit drugs use, at around 22 per cent, with use then declining with increasing age.1 ‘Legal high’ drug use is, however, much harder to ascertain as these drugs are not recorded in the BCS figures, so we can only say qualitatively that use is increasing.

Drug classification

The Misuse of Drugs Act 1971 classifies drugs into three classes: A, B and C, with the most harmful in Class A. This Act determines the legal penalties for possession and supply, with the greatest penalties, and therefore the greatest risks, attached to those in Class A, such as heroin, cocaine and amphetamines.

The Misuse of Drugs Regulations 2001 divide controlled drugs into schedules according to their medicinal use, and potential abuse risks, with those in schedule 1 having no medicinal use and greatest abuse risk, while those in schedules 2-5 have medicinal uses and decreasing risks of abuse.

The Advisory Council on the Misuse of Drugs is the independent scientific body which advises the government on drug related issues. The Council “considers any substance which can or appears to be being misused and which is having or appears to be capable of having harmful effects sufficient enough to cause a social problem”.2 It also investigates any aspect of drug use which appears to be causing particular concern in order to deliver reports which aid policy formation.

Legal highs

These are synthetic substances which mimic the effects of their illegal counterparts. Often sold over the internet or from ‘headshops’ labelled ‘not for human consumption’ or ‘plant feeder’, their use is increasing but knowledge of prevalence and harms and risks is lacking, partly because they are legal. Use is not recorded in the BCS survey and they are relatively new; much of the evidence comes from case reports gathered by various agencies and other people from around the country.

The presumption is that they are less harmful, but this has been shown not to be the case and has been re-enforced by classification of some as controlled drugs in the UK. Other countries such as Sweden have controlled these substances already.

The main group of these is also known as the cathinone drugs and are based on the chemical found in khat. The khat plant is not classified, but its active ingredients, cathinone and cathine are Class C drugs.3 Cathinone can only be used under licence for research, but cathine can be prescribed. Methcathinone is a Class B substance and an analogue of methamphetamine (which is class A).4

The derivatives of the above are not currently controlled drugs in the UK but, at the time of writing, there are plans to change this status. As a result of ongoing research, new legislation was introduced in December 2009 to class some of these drugs as Class B or C drugs, attracting the same penalties as other much more widely known drugs, such as amphetamines, ecstasy, cannabis and barbiturates.

Cathinones are split into two groups in terms of classification, with cathinone in Class C, while methcathinone is class B because it is an analogue of methamphetamine. Most of the substituted cathinones are not yet controlled5 but this could change in the near future.

Cathinones are related to amphetamine compounds such as ecstasy, therefore causing similar effects of alertness and euphoria and also anxiety and paranoid attacks. It appears that mephedrone (4-methylmethcathinone) causes periods of compulsive use. It is often marketed on the internet as ‘plant food’, a chemical ‘not fit for human consumption’, or ‘plant feeder’.

Salvia has been known about for hundreds of years and comes from the soft leaves of the Mexican plant Salvia divinorum. The ACMD will also consider it in the list of drugs which could be classified.6

New controlled drugs

The drugs in the table overleaf were classified under the Misuse of Drugs legislation in December 2009, following increasing numbers of reports and research into their harmful effects. It is not yet known whether this change in classification will affect the sales or prevalence of the drugs. What is has served to do, however, is increase awareness of the compounds and their risks. Combining these drugs, and all other drugs of abuse, with other substances, including alcohol and benzodiazepines, increases the risk of overdose and other harmful effects.

BZP and the piperazines

  • Synthetic stimulants derived from piperazine (a worming agent).
  • They are an alternative to ecstasy or amphetamine, but with less potent effects.
  • Sold online as ‘plant food’ or ‘not fit for human consumption’.
  • There is little known about health risks as insufficient large scale studies have been carried out, but there have been reports of otherwise healthy people suffering heart attacks after taking BZP, and increased risk with pre-existing hypertension or heart condition.
  • Piperazines can in rare cases cause a serotonin syndrome which can be fatal.
  • Piperazines are used in industry to make plastics, resins and brake fluids, among other things.7

Synthetic cannabinoids

  • Mimic the effects of THC, the chemical found in cannabis and are sprayed onto a mix of inert, base plant products and smoked.
  • They are also known as ‘spice’, which is a herbal mixture not harmful in itself.
  • There is no way of telling at the time what has been sprayed onto the base leaves. Base leaves used include blue water lily
    (Nymphaea), and Siberian motherwort (Leonurus sibiricus).8
  • Little is known about the likelihood of dependency and withdrawal symptoms, but as it is related to cannabis similar symptoms are likely, including irritability, mood changes, diarrhoea, and difficulty sleeping. 9
  • Placed in schedule 1 of the 2001 regulations as they have no recognised medical use. Nabilone is an exception to this, being placed in schedule 2.

GBL (gamma-butyrolactone)

  • An anaesthetic with sedating, rather than painkilling, effects.
  • Promotes slow wave sleep, during which growth hormone is produced, which is why it is used by bodybuilders.10
  • Metabolised rapidly to GHB, which is a Class C drug.
  • Also known as liquid ecstasy, because it has similar effects, but has no chemical relationship.
  • Linked with sexual assaults, but the extent of this is unclear.10

Anabolic steroids

  • Fifteen more anabolic steroids have been reclassified as Class C drugs, including danazol, gestrinone and prostanozol, as well as growth promoters zeranol and zilpaterol.11
  • They can be taken orally as tablets or liquids and also injected.
  • All the same effects and risks apply to these as to those steroids already classified under the Misuse of Drugs Act, including liver abnormalities, hypertension, reduction in sperm count and increased masculinisation and sex drive in women.
  • Physical dependence is not a risk with steroids, but psychological dependence is, in that the person will often feel depressed after stopping their use.

Advice for parents

The following advice can be given to parents concerned that their child is abusing drugs. The most important thing to emphasise is that they should not jump to conclusions (particularly as many of the signs of potential drug use are quite non-specific). They should not panic and should talk to their child. They should also try not to feel guilty – there are many reasons why a child could be using drugs, and there is no social class divide for drug use.

There any many sources of support and information available to parents, which are listed in the resources. Parents may feel more at a loss where legal highs are concerned, but the following advice is still relevant, especially where there is much less known about them and their longer-term effects.

Possible signs of drug use include the following:

  • Changes in appearance, interests, eating and sleeping habits;
  • Mood changes, such as increased irritability;
  • Lying;
  • Possession of leaves or sachets;
  • Different smells;
  • Theft;
  • Episodes of intoxication, such as slurred speech and staggering;

Before broaching the subject of suspected drug use with the child, the parent is well advised to find out as much as possible prior to the conversation. And remind them that there is no evidence that just because a child has started to use drugs that they will definitely become problem users.

Other general advice includes

  • Set aside a time and place to talk;
  • Avoid blame;
  • Ask open-ended questions;
  • Do not assume anything;
  • Ask someone to help;
  • Set clear limits – the child needs to know how the parent feels;
  • Write down/prepare what you want to bring up and how (this may not go according to plan, but being prepared for what they want to ask can help).

What to do in an emergency

Slightly different approaches are needed according to the drug type used, but it is important not to give the casualty anything, as this could complicate the situation. If the user is unconscious or very drowsy they should be placed in the recovery position and an ambulance called. Medical help should always be sought if there are any concerns.

Drugs such as amphetamines, cannabis and ecstasy can make the user feel tense and panicky, whereas heroin, aerosols, alcohol and tranquilisers (among others) will make the user drowsy. In both cases, remaining calm and reassuring is important. The feelings will pass and long, slow and deep breaths should be taken. Caffeine should not be given in an attempt to rouse the user.

Further information

Please visit www.thepharmacist.co.uk for a full list of references.

FRANK: www.talktofrank.com DirectGov: The Parents and Crime and Justice areas have sections on drugs: www.direct.gov.uk Addaction: The UK’s largest drug and alcohol treatment charity dedicated to helping all those affected by drug and alcohol use DrugScope: An independent centre of information and expertise on drugs CPPE Open learning programme: Substance Use and Misuse

Rosemary Blackie is member of the Pharmacist Substance Misuse Network and a community pharmacist in Sheffield.


Want news like this straight to your inbox?


Latest News

Cambridgeshire pharmacies dispensing £4m a year worth of OTC medication
Cambridgeshire and Peterborough CCG spends over £4m annually on prescribing medicines that patients could buy...
Nexium now available over the counter
Nexium Control tablets are now available for general sale. Previously only available on prescription, the...
Pharmacy management of dry eyes
A moist, healthy eye surface is essential for normal vision and this requires a sufficient...