Mephedrone (4-methylmethcathinone) is a stimulant drug, which means it speeds up the messages traveling between the brain and body.1 Mephedrone is classed among New Psychoactive Substances (NPS), a range of drugs that have been designed to produce effects similar to those of established illicit drugs. It was originally marketed online as a plant fertiliser or ‘research chemical’.1 Mephedrone comes in different forms, including: white powder with a yellowish tinge crystals capsules pills.2