Flephedrone is a synthetic stimulant drug of the amphetamine and cathinone classes. It is chemically similar to the cathinone compounds found in the khat plant of eastern Africa. It comes in the form of a powder, which users can swallow, snort, inject or insert rectally producing effects which are somewhat similar to MDMA, amphetamine, and cocaine. Almost nothing is known about the long-term effects of flephedrone due to its short history of its use. The exact toxic dosage is unknown.

World Health Organization 2014:
4-FMC, has emerged in recent years as a recreational psychostimulant. Its synthesis was first published in 1952 in order to explore the potential for antithyroidal, antibacterial and bacteriostatic properties. Publications about the detection of 4-FMC obtained from Internet sources and test purchases started to appear from 2009 onwards. The first official notification submitted to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) by a European member state was 2008. Since then, it has been detected across the globe as a reflection of modern forms of trade within a globalised world. As was the case with many other emerging substances with psychoactive properties, commonly used terms include "legal highs", "bath salts" or "new psychoactive substances" (NPS) in the attempt to highlight the fact that many, if not most, did not originally fall under any legislative control and that detailed data on both pre-clinical and clinical levels were normally less well explored. The amount of research data on 4-FMC is comparatively small in comparison with other cathinones.

World Health Organization 4-FMC (PDF 22 pages):
https://legal-high-inhaltsstoffe.de/sites/default/files/uploads/flephedron_-_4-fmc.pdf

On the drug forums, the users report effects comparable to MDMA and mephedrone. Flephedrone is usually administered orally, nasally or rectally over 2 -4 hour period in divided doses totaling 200-700 mg. Some users find flephedrone less pleasurable, more addictive and "toxic" than mephedrone and methylone. Fatigue, sleep deprivation and loss of appetite are the common after effects, similar to other cathinones. The recreational use of flephedrone was first reported in 2009

Flephedrone:

• A stimulant drug of the cathinone chemical class
• Has been sold online as a designer drug starting in 2008.

Flephedrone has only a short history of human use and its toxicity is not well established