New PsychoactIve Substances - Evidence Review

This paper summarises the key information currently available on New Psychoactive Substances (NPS) and evidence gaps. Data on Scotland is presented in the context of UK and international evidence.

2 Main Types Of NPS Available

Key Findings

  • NPS can contain legal substances, illegal substances, or even a mixture of both.
  • They can be grouped according to their chemical names, or, perhaps more usefully, by their intended effects on the user (e.g. stimulants).
  • The number of new drugs available is constantly changing and growing - by 2013, over 300 NPS had been identified in Europe.

2.1 The new drugs market involves an overlap of two broad groups of drugs: those sold directly on the illicit market with those sold as 'legal highs'. Some NPS are added to or sold in place of established illicit drugs, such as ecstasy, and some 'legal highs' cross over into the illicit markets once controls are put in place (EMCDDA, 2013a). Seized substances marketed as 'legal highs' have been found to contain controlled drugs - for e.g. a Home Office Forensic Early Warning System study found that 19% of internet test purchases of 'legal highs' contained a controlled substance (Home Office, 2012).

Number and types of NPS drugs available

2.2 The UNODC report[2] (UNODC 2013a) identifies 6 main groups of drugs that are present in the NPS market: synthetic cannabinoids (e.g. Spice); synthetic cathinones (e.g. mephedrone); ketamine; phenethylamines (e.g. benzofury); piperazines (e.g. BZP); and plant based substances. It also reports on a 7th group of miscellaneous substances that contain recently identified NPS (e.g. tryptamines) that don't fit into any of these groups. Other pharmaceutical medications not used within the UK, for example benzodiazepines such as Phenazepam, have also been included within the broad definition of NPS by the ACMD and the UK National Programme on Substance Abuse Deaths (np-SAD). As well as these chemical groupings, NPS can also be categorised according to their main characteristics, or effects on the user. For instance, DrugWatch has produced 'The Drugs Wheel' ( which groups drugs under: stimulants; empathogens; psychedelics; dissociatives; cannabinoids; depressants; and opioids. This also helpfully shows which of these drugs are currently controlled in the UK and which are still legal.

2.3 The emergence of NPS in the drug markets has gained pace over the last decade. A record number of 81 substances were detected for the first time in Europe in 2013, up from 73 substances in 2012, 49 in 2011, 41 in 2010, and 24 in 2009 (EMCDDA, 2014). The 81 NPS detected in 2013 included: 29 new synthetic cannabinoids; 13 new substituted phenethylamines; 7 synthetic cathinones; one new piperazine; one new tryptamine; and 30 miscellaneous 'other' substances that do not fit into the main categories above. In total, over 300 NPS had been identified by member states by mid-2013 (EMCDDA, 2014[3]).

2.4 The market for NPS is rapidly changing. Prior to 2008, most countries reported ketamine, followed by piperazines and non-controlled phenethylamines as NPS. Over the period 2008-2012, most countries identified synthetic cannabinoids (e.g. Spice), followed by synthetic cathinones (e.g. mephedrone) (UNODC, 2013b).


Email: Fiona Fraser

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