What's three,four-DMMC?three,four-DMMC, often called 3,four-Dimethylmethcathinone, is often a artificial stimulant belonging to the cathinone family members. Cathinones are psychoactive substances which have effects similar to amphetamines, and 3,four-DMMC is no exception. It shares structural similarities with mephedrone (4-MMC), another effective