MDMA (3,4-methylenedioxy-N- methylamphetamine) is an entactogenic drug of the phenethylamine and amphetamine classes of drugs. MDMA has become widely known as "ecstasy" (shortened to "E", "X", or "XTC"), usually referring to its street pill form, although this term may also include the presence of possible adulterants.
MDMA can induce euphoria, a sense of intimacy with others, and diminished anxiety. Many studies, particularly in the fields of psychology and cognitive therapy, have suggested that MDMA has therapeutic benefits and facilitates therapy sessions in certain individuals, a practice for which it had formally been used in the past. Clinical trials are now testing the therapeutic potential of MDMA for post-traumatic stress disorder (PTSD) and anxiety associated with terminal cancer.
MDMA is criminalized in most countries (though some important civil society initiativessuch as the Global Commission on Drug Policy consider educating the public about the drug more important than curtailing supply) and its possession, manufacture, or sale may result in criminal prosecution. Some limited exceptions exist for scientific and medical research. For 2008 the UN estimated between 10–25 million people globally used MDMA at least once in the past year. This was broadly similar to the number of cocaine, amphetamine and opiate users, but far fewer than the global number of cannabis users. It is taken in a variety of contexts far removed from its roots in psychotherapeutic settings and is commonly associated with dance parties (or "raves") and electronic dance music.
Regulatory authorities in several locations around the world have approved scientific studies administering MDMA to humans to examine its therapeutic potential and its effects.