Synthetic cathinones are related to the parent compound cathinone (Figure 1), one of the psychoactive principals in khat (Catha edulis Forsk). Cathinonederivatives are the β-keto (βk) analogues of a communicate phenethylamine. The group includes several substances that have been used as active pharmaceutical ingredients (API) of medicinal products. Since the mid-2000s, unregulated ring-substituted cathinonederivatives have appeared in the European recreational drugs market. The most commonly available cathinonessold on the recreational market in the period up to 2010 appear to be mephedrone and methylone . These products are usually encountered as highly pure white or brown powders. Ring-substituted cathinonederivatives are claimed to have effects similar to those of cocaine , amphetamine or MDMA (ecstasy), but little is known of their detailed pharmacology. Apart from cathinone, methcathinone and two API ’s amfepramone and pyrovalerone, cathinonederivatives are not under international control.