I just want to point this out . The initial paper that really got the press and legislature against MDMA turned out to have accidentally used Methamphetamine , already known to be neurotoxic , in place of MDMA . The article was later retracted , but not before having influenced public opinion on the effects of MDMA dramatically . Of course injecting rats with Meth for three days straight at absurd doses will be braindamaging . This commonly seen was part of Ricaurte ' s study . Here ' s an archivemdmard 011604 . html that makes a lot of points on this subject , and a few more r e s e a r c h m d m a o t h e r m d m a r e s o u r c e s m d m a s c i e n t i f i c l i t e r a t u r e g o v ernmenthearingsandarchive 364 m d m a s c i e n t i f i c l i t e r a t u r e g o v ernmenthearingsandarchive to get you going . Originally retracted articleThere ' s still debate about inferring data from rats , and the determination that MDMA is extremely neurotoxic in human beings isn ' t quite agreed upon yet . Note that your article claims Experimental studies indicate that MDMA damages serotonergic neurons in animals and possibly in humans , and it would seem that they were using animal data to make inferences . Amphetamine itself is a good example of differing reactions to a drug ' s toxicity , as it doesn ' t have directly neurotoxic effects on human beings only indirectly , such as through excitotoxicity and oxidative stress , but is damaging to rats and primates , though Meth elicit neurotoxic effects in human beings . It ' s possible that the changes elicited by MDMA are plastic , and not permanent , and the article you linked was making a broad generalization on the implications of the adverse effects on RATS with respect to human beings . Likewise , all the articles on MDMA neurotoxicity tend to make broad generalizations based on animal models , rather than actual human data . This r i s k s s c i e n c e a n d s t a t i s t i c s t e c h n i c a l f a q m d m a e c s t a s y m o l l yneurotoxicitybraindamage is well sourced , and contains a few longterm MDMA studies . I ' m not making the claim that it isn ' t neurotoxic , but rather , public belief even a lot of the belief in the scientific and legislative communities in MDMA toxicity was kickstarted by a completely fucked up study , and people continuously try to make inferences from animal models that may not necessarily be accurate in human beings .