Actually, I believe that what the UAs detect is the part of MDMA that is an amphetamine - if I'm not mistaken. So if you take ANY tabs and they are checking for methamphetamines - you'll get a dirty UA. This is from the National Institute of Drug Addiction's (NIDA) classification of drugs. They list: Methamphetamines, w/ ecstasy as a sub-listing. Most drug tests can detect methamphetamines, cocaine and marijauna. Unless they are sending it to a lab or doing a hair test - most of the other stuff your local police and probation officers won't be able to detect. Hallucinogens are the hardest to test for. Did I mention I'm a Criminologist? I know all of this for purely professional reasons!