4-MEC is a synthetic stimulant with empathogenic effects that is chemically similar to methcathinone. It became available online in 2010 and has been sold as replacement for 4-methylmethcathinone (mephedrone). It has an extremely short history of human use. As of 2011, it is most often found as a powder (either represented as 4-methylethcathinone or included in powder products that don't specify their active ingredients) and has appeared in some samples of "NRG-2", although it has also been found in tablet form.
Some reports of 4-methylethcathinone use involve redosing ("boosting" or "bumping") multiple times. Users sometimes mix oral and insufflated, taking some 4-methylethcathinone orally, then insufflating some, then taking more orally. Because of the common desire to recapture the pleasurable initial high, redoses are sometimes higher than the initial dose or are spaced closely together in time. Many users report having difficulty not redosing after using a strong dose if more 4-methylethcathinone is available when they are starting to come down. Experience reports in which users find themselves unexpectedly consuming a gram or more of 4-methylethcathinone are common.
Some users have injected the drug intravenously. This requires heating the water/4-MEC solution in order for 4-MEC to dissolve. Injecting 4-MEC appears to be rough on veins and is sometimes accompanied by a burning sensation; for this reason 4-MEC should be diluted as much as possible. Intravenous dosages are comparable to oral ones, although more care should be given to safety (with regard to possibility of overdose and long-term effects).
^Brandt, S. D.; Sumnall, H. R.; Measham, F.; Cole, J. (August 2010). "Analyses of second-generation 'legal highs' in the UK: initial findings". Drug Testing and Analysis2 (8): 377–382. doi:10.1002/dta.155. PMID20687197.
^Jankovics, P.; Váradi, A.; Tölgyesi, L.; Lohner, S.; Németh-Palotás, J.; Koszegi-Szalai, H. (2011). "Identification and characterization of the new designer drug 4'-methylethcathinone (4-MEC) and elaboration of a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) screening method for seven different methcathinone analogs". Forensic Science International210 (1–3): 213–220. doi:10.1016/j.forsciint.2011.03.019. PMID21498012.