"Synthetic cathinones are related to the parent compound cathinone (Figure 1), one of the psychoactive principals in khat (Catha edulis Forsk). Cathinone derivatives are the β-keto (βk) analogues of a corresponding phenethylamine. The group includes several substances that have been used as active pharmaceutical ingredients (API) of medicinal products, e.g. amfepramone (diethylpropion; Figure 2). Since the mid-2000s, unregulated ring-substituted cathinone derivatives have appeared in the European recreational drugs market.
New Psychoactive Substances
New or Novel Psychoactive Substances, including synthetic cannabinoids, mephedrone, ketamine, khat, and many others
"The reasons for the more pronounced psychoactive effects and severe and fatal poisoning seen with synthetic cannabinoids are not particularly well understood, but at least two factors are likely to be important: the high potency of the substances and the unintentionally high doses that users are exposed to.
"Synthetic cannabinoids, also known as synthetic cannabinoid receptor agonists, are a group of drugs that mimic the effects of a substance found in cannabis called tetrahydrocannabinol (THC). THC is responsible for many of the psychoactive effects of cannabis which give that feeling of being ‘stoned’ or ‘high’ (Gaoni and Mechoulam, 1964; Huestis et al., 2001; Pertwee, 2005a; Pertwee, 2014). These effects are caused by activating a receptor in the brain called the cannabinoid receptor type 1 (CB1 receptor) (Huestis et al., 2001; Pertwee, 2014).
"Since 2012, a total of 28 new fentanils have been identified on Europe’s drug market. This includes eight substances that were reported for the first time in 2016 and 10 during 2017. During this period, there has also been a large increase in seizures reported by customs at international borders and police at street-level (Figure 4) (see also ‘Reducing the risk of occupational exposure to fentanils’, page 11). While the picture differs widely across Europe, 23 countries have reported detections of one or more of these substances (Figure 5) (2).
"Alongside their legitimate uses as medicines and in research, the fentanils also have a long history of illicit use as replacements for heroin and other controlled opioids. Between 1979 and 1988, more than 10 fentanils that had been made in illicit laboratories were detected on the drug market in the United States (Henderson, 1991). The first was alpha-methylfentanyl, followed by substances such as 3-methylfentanyl and 4-fluorofentanyl. Typically, they were sold as heroin or ‘synthetic heroin’.
"Reflecting consumer demand, the market in new benzodiazepines appears to have grown over the past few years. The EMCDDA is currently monitoring 23 of these substances, including six that were reported for the first time in 2016 and three during 2017. While the overall number of seizures reported by law enforcement during 2016 decreased compared with 2015, the quantity reported increased. More than half a million tablets containing new benzodiazepines such as diclazepam, etizolam, flubromazolam, flunitrazolam and fonazepam were reported during 2016 — which was about 70 % more than in 2015.
"Reflecting their use as legal replacements for cocaine, amphetamine and other controlled stimulants, there were more than 23 000 seizures of synthetic cathinones reported from across Europe in 2016 (Figure 3). These account for almost one-third of the total number of seizures of new substances over the year, and amounted to almost 1.9 tonnes, making synthetic cathinones the most commonly seized new psychoactive substances by quantity in 2016. The EMCDDA is currently monitoring 130 of these substances, including 14 that were reported for the first time in 2016 and 12 during 2017.
"By the end of December 2017, the EMCDDA was monitoring more than 670 new substances that have appeared on Europe’s drug market over the past 20 years. This total includes 51 substances that were reported for the first time during 2017 (Figure 1), namely 13 opioids, 12 cathinones, 10 cannabinoids, 4 phenethylamines, 3 benzodiazepines, 2 tryptamines, 1 arylcyclohexylamine, 1 arylalkylamine, 1 piperidine/pyrrolidine and 4 substances that do not belong to these other groups.
"According to the Crime Survey for England and Wales,238 over the period 2014-2015, 279,000 adults (0.9 per cent of the population aged 16-59) reported the use of NPS. Among young adults (ages 16-24), the prevalence of NPS use was much higher (2.8 per cent), the majority of the users being young men. Herbal smoking mixtures were the most commonly used form of NPS, with 61 per cent of the population aged 16-59 reporting their use.