In New Zealand, it is not included in the Drug Abuse Act 1975, but it is illegal because it resembles controlled substances.  The situation with khat poses a much greater problem in terms of the legality of many psychoactive substances currently available for purchase in the UK and elsewhere. Especially in recent years, synthetic analogues of cathinone have emerged and dominated the market for « legal highs », with substances such as mephedrone and methylone enjoying great popularity (Gibbons and Zloh, 2010). It seems unlikely that it is just a coincidence that Khat`s planning, which has not been regulated for many years, follows the planning of many of these synthetic cathinones so closely (Secretary of State, 2010). As mentioned earlier, it is doubtful that users of these intensely euphoric and significantly more effective synthetic compounds will turn to this much milder herbal drug as a supplement or alternative to their current drug use (Gebissa, 2010; Klein and Metaal, 2010). Nevertheless, khat is now a Class C drug in the UK (POST, 2013), while many new « legal highs » continue to appear on the market, many of which have no history of human consumption and no indication of their potential risks or benefits (Iversen et al., 2013). In the UK, Class C drugs include mild stimulants, sedatives and anabolic steroids. The maximum penalties for possession of Class C drugs are two years` imprisonment and an unlimited fine. According to the Independent Scientific Committee on Drugs, a street drug trade emerged after the illegality of mephedrone, with prices about twice as high as before the ban, at £20-25 per gram.
 In September 2010, Druglink reported that the ban had had a mixed effect on the use of mephedrone, decreasing in some areas, remaining similar in others, and becoming more common in some areas.  In an online survey of 150 users after the ban, 63% said they continued to use mephedrone; Of these, half reported unchanged levels of use (in terms of dosage and frequency) and the other half reported that use had been reduced. Compared to previous surveys, more users bought it from merchants and not on the Internet. The average price per gram was £16, up from around £10 before the ban.  The 2010 Mixmag survey of 2,500 nightclub visitors found that a quarter had used mephedrone in the previous month, that the price had roughly doubled since it was made illegal, and that it was more likely to have been cut with other substances.  Of those who had already used mephedrone before the ban, 75% had continued to use it after the ban. Among the various drugs used by survey participants, users were more concerned.  Interviews with users in Northern Ireland also revealed that the price had roughly doubled since it was illegal to around £30 per gram. Instead of the price rising due to the increased scarcity of the drug, it is believed that it has increased for two other reasons.
First, traders knew that there was still a demand for mephedrone, but were aware that supplies could be exhausted in the future. Second, merchants perceived that customers were likely willing to pay more for an illicit substance.  « Legal Highs » are recreational drugs sold on the Internet and in so-called « headshops » across the UK. They can be purchased and used freely as they are not covered by the Drug Abuse Act 1971. Mephedrone (4-methylmethcathinone) was sold as a « legal high » until April 17, 2010, when it was converted to a Class B drug under the Drug Abuse Act 1971. Many deaths and self-harm have been linked to the use of mephedrone. The effects of mephedrone are thought to be similar to those of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) and have stimulant properties similar to those of cocaine. Not much is known about the effects of mephedrone on mental health. We present a case of dependence and psychosis in a patient using mephedrone (4-methylmethcathinone).
The patient needed inpatient hospital treatment, was treated with antipsychotic olanzapine and recovered well. Mephedrone can be synthesized in several ways. The simplest method, due to the availability of compounds,: 17 is to add 4-methylpropiophenone, dissolved in glacial acetic acid, to bromine, thereby creating an oily fraction of 4`-methyl-2-bromine propiophenone. The oily fraction can then be dissolved in dichloromethane (CH2Cl2) and drops of the solution of another solution of methylamine hydrochloride containing CH2Cl2 and triethylamine added. Hydrochloric acid (HCl) is then added and the aqueous layer is removed and made alkaline with sodium hydroxide before extracting the amine with CH2Cl2. The CH2Cl2 is then evaporated under vacuum, creating an oil that is then dissolved in a non-aqueous ether. Finally, the HCl gas is bubbled through the mixture to produce 4-methylmethcathinone hydrochloride.  This method produces a mixture of both enantiomers and requires knowledge similar to the synthesis of amphetamines and MDMA.
: 17 A 22-year-old man bought 4 g of mephedrone powder over the internet from a Chemical Supplier based in China. He first took 200 mg of mephedrone orally, with no perceived clinical effects, and then injected the remaining 3.8 g intramuscularly into his thighs. Shortly after the injection, he developed palpitations, « blurred tunnel vision, » chest pressure, and sweating, and generally did not feel well; He presented to hospital with persistent characteristics of sympathomimetic toxicity. Her symptoms subsided over the next 4 hours after a single dose of oral lorazepam. Qualitative analysis of the urine and serum sample was performed by gas chromatography with mass spectrometry (GC/MS) detection, both of which positively indicated the presence of 4-methylmethcathinone. Quantitative analysis of the serum sample was performed by liquid chromatography with tandem mass spectrometry detection; The predicted concentration of mephedrone was 0.15 mg/L. Routine toxicological analysis of serum and urine samples using extensive toxicological screening for GC/MS did not reveal any other drugs or alcohol. Media organisations such as the BBC and The Guardian have falsely reported that mephedrone is often used as fertilizer for plants. In fact, drug dealers described it as a « plant-based food » because it was illegal to sell the compound for human consumption.
 In late 2009, British newspapers began calling the drug miaow or miaow (sometimes called miaow meow or miaow miaow), a name that was almost unknown on the street at the time.  In November 2009, the tabloid The Sun published an article claiming that a man had torn off his own scrotum using mephedrone. The story was later published as an online joke on mephedrone.com, later included in a police report with the caveat that it might not be reliable.