4-MEC is a synthetic stimulant with empathogenic effects that is chemically similar to methcathinone. It became available online in 2010. It has been sold as replacement for 4-methylmethcathinone (mephedrone) and has appeared in some samples of "NRG-2". It has an extremely short history of human use. 4-Methylethcathinone is a stimulant with empathogenic qualities. 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 chemicals), though some tablets have been pressed that include 4-methylethcathinone.
Some reports of 4-methylethcathinone use involve redosing ("boosting" / "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. 4-Methylethcathinone Dosages Oral Threshold 15 - 50 mg Light 50 - 100 mg Common 100 - 200 mg Strong 150 - 300+ mg 4-Methylethcathinone Dosages Insufflated (Snorted) Threshold 5 - 25 mg Light 25 - 40 mg Common 40 - 100 mg Strong 100 - 200 mg  Some users have injected the drug IV. This requires heating a water/4-MEC solution in order for the 4-MEC to dissolve. It appears to be rough on veins and sometimes burns and should therefore be diluted as much as possible. The intravenous dosages are comparable to the oral though more care should be given to safety as far as overdose and the long term effects. Little concrete knowledge exists about this compound. There is one report that 4-MEC was used as the active ingredient in fake "Ecstasy" pills in some countries such as New Zealand.
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