[4]: 9 One published study that analysed samples of mephedrone bought using the internet in the UK in 2010 found it was racemic (a mixture of both stereoisomers) and of high purity.

[4]: 13 [24] A survey conducted by the UK National Addiction Centre found 67% of mephedrone users experienced sweating, 51% suffered from headaches, 43% from heart palpitations, 27% from nausea and 15% from cold or blue fingers,[25] indicative of vasoconstriction occurring.

[4]: 13 [14] In 2009, one case of sympathomimetic toxicity was reported in the UK after a person took 0.2 g of mephedrone orally, and after this did not achieve the desired effect, intramuscularly injected 3.8 g mixed with water into his thighs.

[40] Doctors reported she was comatose and suffering from hyponatremia and severe hypokalemia; the woman died one and a half days after the onset of symptoms.

[42] The first death reported to be caused by mephedrone use was that of 46-year-old, John Sterling Smith,[43] who had underlying health problems and repeatedly injected the drug.

[75][76] Mephedrone administration leads to increased extracellular dopamine in the nucleus accumbens, elevated serotonin levels in the frontal cortex, and alterations in brain temperature.

[11][80] Based on the analysis of rat and human urine by gas chromatography and mass spectrometry, mephedrone is thought to be metabolised by three phase 1 pathways.

Knowledge of the primary routes of metabolism should allow the intake of mephedrone to be confirmed by drug tests, as well as more accurate determination of the causes of side effects and potential for toxicity.

Blood or plasma mephedrone concentrations are expected to be in a range of 50–100 μg/L in persons using the drug recreationally, >100 μg/L in intoxicated patients and >500 μg/L in victims of acute overdosage.

The simplest method, due to the availability of the compounds,[4]: 17  is to add 4-methylpropiophenone dissolved in glacial acetic acid to bromine, creating an oil fraction of 4'-methyl-2-bromopropiophenone.

[88] Mephedrone is one of hundreds of designer drugs or legal highs that have been reported in recent years, including artificial chemicals such as synthetic cannabis and semisynthetic substances such as methylhexanamine.

"[91] After the initial description of mephedrone's qualitative effects by Kinetic, the drug was commercially introduced in Israel by a mathematician named Ezekiel Golan or "Dr.

[105] In January 2010, Druglink magazine reported dealers in Britain spent £2,500 to ship one kilogram from China, but could sell it for £10 a gram, making a profit of £7,500.

[107] In March 2011, the International Narcotics Control Board published a report about designer drugs, noting mephedrone was by then being used recreationally in Europe, North America, Southeast Asia, New Zealand and Australia.

[112] Fiona Measham, a criminologist at the University of Lancaster, thought the emergence of mephedrone was also related to the decreasing purity of ecstasy and cocaine on sale in the UK,[48] a view reinforced in a report by the National Treatment Agency for Substance Misuse.

[91] According to John Ramsey, a toxicologist at St George's, University of London, the emergence of mephedrone was also related to the UK government banning the benzylpiperazine class of drugs in December 2009.

[121] Parallels were drawn between the media coverage of mephedrone and a piece of satire by Chris Morris in 1997 on Brass Eye when he tricked public figures into talking of the dangers of taking the fictional legal drug "cake".

[124] Detailed interviews with users in Northern Ireland similarly found that few purchased mephedrone online, with most interviewees citing concerns that their address would be traced or that family members could intercept the package.

He said the decision by the Home Secretary was "unduly based on media and political pressure" and there was "little or no discussion about how our recommendation to classify this drug would be likely to impact on young people's behaviour.

"[129] Some former members of the ACMD and various charity groups expressed concern over the banning of the drug, arguing it would inevitably criminalise users, particularly young people.

[132] The parliamentary debate was held on 8 April, one day after the 2010 general election had been announced, meaning it was during the so-called "wash-up period" when legislation is passed with little scrutiny.

[133] In an interview conducted in July 2010, when he was no longer a minister, Johnson admitted the decision to ban mephedrone was sped up after widespread reporting of deaths caused by the drug, and because the government wished to pass the law before parliament was dissolved prior to the upcoming general election.

[122] Evan Harris, then the Liberal Democrat science spokesman, stated the ACMD "was not 'legally constituted'" as required by the Misuse of Drugs Act, when the report on cathinones was published, since after Taylor resigned, it lacked a veterinary surgeon.

[142] The 2010 Mixmag survey of 2,500 nightclubbers found one quarter had used mephedrone in the previous month, the price had roughly doubled since it was made illegal, and it was more likely to be cut with other substances.

[168] In May 2010, the Republic of Ireland made mephedrone illegal,[169][170][171] followed by Belgium,[172] Italy,[173] Lithuania,[174] France[175][176] and Norway[177] in June and Russia in July.

The Drug Enforcement Administration (DEA) states, as an analogue of methcathinone, possession of mephedrone can be controlled by the Federal Analog Act, but according to the Los Angeles Times, this only applies if it is sold for human consumption.

Except as authorised by law, this action made possessing and selling mephedrone or the products that contain it illegal in the US for at least one year while the DEA and the United States Department of Health and Human Services conduct further study.

[206] A survey conducted in late 2009 by the National Addiction Centre (UK) found 41.3% of readers of Mixmag had used mephedrone in the last month, making it the fourth-most popular drug amongst clubbers.

[15] An Irish study of people on a methadone treatment program for heroin addicts found 29 of 209 patients tested positive for mephedrone usage.

"[208] Les King, a former member of the ACMD, has stated mephedrone appears to be less potent than amphetamine and ecstasy, but that any benefit associated with this could be negated by users taking larger amounts.