Mephedrone is the common name for 4-methylmethcathinone. The systematic IUPAC name is: (RS)-2-methylamino-1-(4-methylphenyl)propan-1-one. It is a synthetic ring-substituted cathinone closely related to the phenethylamine family, differing only by a keto functional group at the beta carbon. The molecular formula for mephedrone is C11H15NO, equating to a molecular weight of 177.242 g/mol. Chemical Abstracts Service (CAS) registry numbers of mephedrone are 1189805-46-6 (base) and 1189726-22-4 (hydrochloride salt). In addition to mephedrone, positional isomers of methylmethcathinone include 2-methylmethcathinone and 3-methylmethcathinone.

Mephedrone hydrochloride salt is a white powder, while its free base is a yellowish liquid at ambient temperature. Mephedrone is typically sold as crystalline powder — stable, watersoluble, white or lightly coloured hydrochloride salt; most probably as a racemic mixture of the R and S enantiomers. The powder is readily soluble in water and can be dissolved for oral/rectal use or for injection. Mephedrone has also been found as capsules containing powder and as tablets pressed from powder.

Mephedrone is metabolised by a number of pathways to the following metabolites: normephedrone, nor-dihydro mephedrone, nor-hydroxytolyl mephedrone, 4-carboxy-dihydro mephedrone, hydroxytolyl mephedrone. It is thought that the hydroxytolyl mephedrone and norhydroxytolyl mephedrone metabolites are partly excreted as glucuronide and sulphate conjugates. There is no data available to be able to determine how long either mephedrone or its metabolites remain detectable, nor on their stability in biological specimens.

Gas chromatography coupled with mass spectrometry (GC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS) techniques have been developed for the analysis of mephedrone and some of its metabolites/precursors. The mass-spectrometry technique does not distinguish between methylmethcathinone isomers; however nuclear magnetic resonance spectroscopy (NMR) and other techniques allow the isomers to be differentiated. Immunoassay field tests for methamphetamine give false positive reactions with some cathinone derivatives.

Mephedrone has no established or acknowledged medical value or use (human or veterinary) in the European Union. There is no marketing authorisation (existing, ongoing or suspended) for mephedrone in the European Union or in the Member States. There is no information that mephedrone is used for the manufacture of a medicinal product or an active pharmaceutical ingredient (API) of a medicinal product in the European Union. There remains a theoretical possibility that mephedrone could be used for the synthesis of some API of veterinary or human medicinal products (e.g. ephedrine, pseudo-ephedrine and pyrovalerone). No data exists to suggest that this is currently the case but it should be noted that there is no European Union database on the synthetic routes of all registered medicinal products.

Mephedrone is commercially available from suppliers on the Internet where it can be purchased in bulk. There are no indications that mephedrone may be used for any other legitimate purposes. There are no known uses of mephedrone as a component in industrial, cosmetic or agricultural products.

Mephedrone is reported to be used in single doses of between 5–250 mg, although due to short-lived effects the total doses used per session may be greater, possibly between 0.5–2 g. Onset of desired effects is typically seen within 15–45 minutes of oral ingestion and a few minutes after nasal insufflation. Users report that the desired effects last approximately 2–3 hours and therefore that they may consume multiple doses during a session to prolong the duration of the desired effects.

There are no formal pharmacodynamic studies looking specifically at mephedrone. Based on its chemical structure, it is likely that it has a similar mechanism of action to other stimulant drugs (blocks reuptake of, and stimulates the release of stimulant neurotransmitters such as serotonin, dopamine and norepinephrine). This is further supported by the sympathomimetic effects (dilated pupils, tachycardia, hypertension, agitation) seen with mephedrone use that are similar to other stimulant drugs such as MDMA and cocaine.

There are no published formal studies assessing the psychological and/or behavioural effects of mephedrone in humans. In addition, there are no animal studies on which to base an extrapolation of potential effects. However, users report that the desired psychological and behavioural effects of mephedrone include euphoria, general stimulation, enhanced music appreciation, elevated mood, decreased hostility, improved mental function and mild sexual stimulation. These effects are broadly comparable to those reported for better-studied stimulant drugs.

5)

(6)