 Its activity at the dopamine transporter is six times stronger than at the norepinephrine transporter and it is virtually inactive at the serotonin transporter.MDPV remained an obscure stimulant until around 2004 when it was reportedly sold as a designer drug.Until banned in 2011, products containing MDPV and labeled as bath salts were sold as recreational drugs in gas stations and convenience stores in the United States, similar to the marketing for Spice and K2 as incense.