Second Thoughts on 3,4-Methylenedioxymethamphetamine (MDMA) Neurotoxicity

To the Editor.—  Recent attention has been drawn to the purported neurotoxic dangers associated with 3, 4-methylenedioxymethamphetamine (MDMA). Price et al¹ have attempted to assess possible serotonergic neurotransmitter damage by contrasting serum prolactin response to the challenge with intravenous L-tryptophan in subjects with a history of MDMA use vs control subjects. Their primary finding was a blunted rise in the expected serum prolactin level in MDMA users, but not to a statistically significant degree. The importance of this finding appears to be questionable and perhaps misleading. Even if the data had yielded a statistically significant result, would such a correlation necessarily imply causation?A methodological limitation to the study would appear to be that subjects were not adequately screened on selection to exclude those who were using other psychotropic drugs. There is no mention that toxicology screens were ever performed. In fact, three subjects (33%) admitted to marijuana use