Mephedrone also known as Meow Meow, MCAT & Drone is perhaps the best well known of the recent designer drugs and became widely available for a period between 2004 and 2010. It is now illegal in Europe and the US.
Similar to Cathinone in its structure it has been referred to as the poor mans cocaine. No current drug testing kit for Mephedrone exists to reliably detect either the base compound or its metabolites in either urine saliva or blood.
Claims have been made that Methamphetamine drug tests will detect Mephedrone. There is no chemical similarity between the 2 drugs and Methamphetamine drug tests should always give a negative result if tested on Methedrone. Neither is there any evidence that Methedrone has been mixed in Methamphetamine, so the claim that methamphatamine drug test kits can been used to screen for Mephadrone use are without any factual base.
Since being regulated substitution with similar compounds has occurred, again none of these are similar chemically to Methamphetamine. All remain covered by current UK and EU legislation, but the mephedrone remains available via illegal routes and remains popular.