Mephedrone, also known as 4-methylmethcathinone (4-MMC), or 4-methylephedrone, is a synthetic stimulant and entactogen drug of the amphetamine and cathinone classes. Slang names include meph, drone, and MCAT. It is reportedly manufactured in China and is chemically similar to the cathinone compounds found in the khat plant of eastern Africa. Mephedrone was first synthesised in 1929 but did not become widely known until it was rediscovered in 2003. By 2007 mephedrone was reported to be available for sale on the internet, by 2008 law enforcement agencies had become aware of the compound and by 2010 it had been reported in most of Europe, becoming particularly prevalent in the United Kingdom. It comes in the form of tablets or a powder, which users can swallow, snort or inject, producing similar effects to MDMA, amphetamines and cocaine. As well as producing the intended stimulant effects, negative side effects occur when mephedrone is used, with teeth grinding the most common. The metabolism of mephedrone has been studied in rats and humans, and the metabolites can be detected in urine after usage. Nothing is known about the potential neurotoxicity of mephedrone, but scientists have suggested possible dangers associated with its use based on its similarity to other drugs. Several people have died after consuming mephedrone, but some deaths that the media attributed to the drug were later determined to have been caused by other factors.

Mephedrone is one of hundreds of designer drugs or legal highs that have been reported in recent years, alongside with herbs such as Salvia divinorum, artificial chemicals such as synthetic cannabis and semi-synthetic substances such as methylhexaneamine. These drugs are primarily developed to avoid being controlled by laws against illegal drugs, thus giving them the label of designer drugs. Between the summer of 2009 and March 2010 the use of mephedrone grew rapidly in the UK, with it becoming readily available at music festivals, head shops and on the internet. A survey of Mixmag readers in 2009, found that it was the fourth most popular street drug in the United Kingdom, behind cannabis, cocaine, and ecstasy. The drug is used by a diverse range of social groups. Whilst the evidence is anecdotal, researchers, charity workers, teachers and users have reported widespread and increasing use of the drug. The drug's rapid growth in popularity was believed to be related to both its availability and legality. On 7 April 2010 the Misuse of Drugs Act 1971 (Amendment) Order 2010 was passed by parliament, making mephedrone and other substituted cathinones, Class B drugs from 16 April 2010. Prior to the ban taking effect, mephedrone was not covered by the Misuse of Drugs Act 1971. It was however an offence under the Medicines Act to sell it for human consumption, so it was often sold as "plant food" or "bath salts" although, as it has no use as these products, this too was possibly illegal under the Trade Descriptions Act 1968.

Users have reported that mephedrone causes euphoria, stimulation, an enhanced appreciation for music, an elevated mood, decreased hostility, improved mental function and mild sexual stimulation; these effects are similar to the effects of cocaine, amphetamines and MDMA. These effects last different amounts of time, depending on the way the drug is taken. When taken orally, users report they can feel the effects within 15–45 minutes, when snorted the effects are felt within minutes and peak within half an hour. The effects last for between two and three hours when taken orally or nasally, but only half an hour if taken intravenously. Almost nothing is known about the long-term effects of the drug due to the short history of its use. BBC News reported that one person who used the drug for 18 months became dependent on the drug, in the end using it twice a week, had to be admitted to a psychiatric unit after he started experiencing hallucinations, agitation, excitability and mania. Very little is known about the pharmacology of mephedrone. Writing in the British Medical Journal, psychiatrists stated that given its chemical structure, "mephedrone is likely to stimulate the release of, and then inhibit the reuptake of monoamine neurotransmitters". The cathinone derivatives methcathinone and methylone, act in a similar way to amphetamines mainly acting on catecholamine transporters so it is expected that mephedrone also acts in this way. The actions of amphetamines and cathinones are determined by the differences in how they bind to noradrenalin, dopamine and serotonin transporters.

Formal Chemical Name (IUPAC)
(RS)-2-methylamino-1-(4-methylphenyl)propan-1-one

References

http://en.wikipedia.org/wiki/Mephedrone

http://www.bbc.co.uk/newsbeat/10004383