Mephedrone (4-methylmethcathinone) is a synthetic cathinone found mostly as a powder but also as tablets. It has no established or acknowledged medical value or use (human or veterinary) in the European Union. There are no indications that mephedrone may be used for any other purposes. It is commercially available from suppliers on the Internet where it can be purchased in bulk. The main precursor of mephedrone, 4-methylpropiophenone, is also commercially available.

The physical effects reported by mephedrone users are typical of other stimulants and may be particularly similar to MDMA. There are no published formal studies assessing the psychological and/or behavioural effects of mephedrone in humans and in animals. Furthermore, in the absence of representative studies, prevalence rates are difficult to estimate. The available studies are limited in number, largely preliminary and geographically restricted, and reliant on user accounts. Taken as a whole, the scientific evidence base available for drawing conclusions is limited and this proviso should be borne in mind when interpreting the findings of the risk assessment exercise.

Many of the questions posed by the lack of evidence on the health and social risks of mephedrone, as for any new psychoactive substance, could be answered through timely research. Further studies are needed, especially with respect to potential toxicity, potential to
produce dependence and the social consequences related to mephedrone use.

There is sufficient evidence that mephedrone can be an attractive drug for those seeking stimulant psychoactive effects for recreational purposes. In the short time that it has been available, mephedrone has established itself in some countries as a sought-after substance in its own right, for which some users express preference over other established stimulant drugs. Overall, the psychoactive properties of this drug would suggest it has a potential for diffusion to other populations and countries, which may constitute a health and social threat. Future diffusion is likely to be influenced by many factors including the availability and quality of other stimulant drugs.

It appears that the effect profile and clinical presentations of mephedrone intoxications share some features seen with MDMA and some features seen with cocaine. The current evidence base does not allow an accurate assessment to be made of the extent to which mephedrone users are likely to experience health problems. However, sufficient data are available to allow the Committee to conclude that some users of the drug do experience acute health problems. In general, these are similar to the acute problems reported with use of illicit stimulants. Moreover, both user reports and the psychoactive properties of mephedrone would suggest that the drug is able to produce dependence in users. Current data are not sufficient to determine the relative dependence-producing potential of mephedrone. However, a number of factors would suggest that this is a concern that merits further investigation. There have been a very limited number of deaths reported to be related directly to the use of mephedrone.

The chronic health effects related to the consumption of mephedrone remain virtually unknown. No studies have been published investigating the potential for chronic mephedrone toxicity associated with mephedrone use, including reproductive toxicity, genotoxicity and carcinogenic potential.

The social consequences associated with the use of any drug are likely to be influenced by a number of factors. To date, different patterns of use have been observed. Mephedrone has established itself very quickly within the recreational drug market within at least two Member States. However, in another Member State initial growth in use/availability appears to have been followed by a decline. Limited use of mephedrone among problem drug users has also been reported, including mephedrone being injected. Based on the available evidence, it is difficult to draw any firm conclusions on the likely social risks associated with mephedrone, but given the speed at which the drug has become established and its potential attractiveness to different groups of drug users, there is a need for ongoing vigilance.

This drug has been marketed over the Internet and through specialist suppliers; it is also being sold by established street dealers. Organised crime has noted the potential for legally purchased stimulants to be sold in the illicit drugs market, but international trafficking and the involvement of organised crime with mephedrone is relatively limited at present.

The Committee notes that a decision to control this drug has the potential to bring with it both positive and negative consequences. Potential positive consequences may include reduced availability and use of the drug. It is important, however, to anticipate and minimise any potential negative consequences of control. Control measures could create an illegal market in mephedrone with the associated risk of criminal activity. Furthermore, control should not inhibit the gathering and dissemination of accurate information on mephedrone to users and to relevant professionals.

(9) One illustrative example of using import legislation is provided by the United Kingdom. Before entry into force of control under drugs legislation in the United Kingdom, the Home Secretary wrote to local authorities urging them to use powers under the Consumer Protection from Unfair Trading Regulations 2008 and consider enforcement steps to be taken to ensure mephedrone is not advertised as a fertiliser or bath salts, following ACMD confirmation that mephedrone has no such use. They could also use medicines legislation to seize samples labelled for 'human consumption'. Following advice from the ACMD on harms, mephedrone and related compounds were banned from import by removing these substances from the Open General Import Licence (OGIL).