Is MDMA ('Ecstasy') neurotoxic in humans? An overview of evidence and of methodological problems in research.

Evidence from research with a range of animal species, from rodents to non-human primates, has shown that MDMA (+/-3, 4-methylenedioxymethamphetamine) is neurotoxic. This article explores the evidence that MDMA may be neurotoxic in humans by briefly overviewing three types of research: (1) neurobiological, (2) psychological/somatic and (3) psychiatric. The first type of evidence derives from neuropharmacological and neuroendocrine studies, the second type focuses on psychological function and somatic symptoms in MDMA users, and the third involves studies of psychiatric cases in people who have taken MDMA. Evidence from these types of studies is indirect and differs in the degree to which any causative links are implied between observed effects, MDMA use and human neurotoxicity. These issues are critically discussed within the context of the wide-ranging methodological problems in human research with MDMA.