The Guardian carries a story about a man who took 40,000 Ecstasy pills over nine years. The man sounds a wreck – paranoia, hallucinations, depression and extreme short-term memory loss, despite not having taken Ecstasy for seven years.
The story provides a good illustration of some of the methodological problems with proving that MDMA use is dangerous
This was an extreme case – does normal recreational use of ecstasy have the same effects, but less, or is the amount consumed by most people well within their ability to safely process the drug? Many animal studies which show harmful effects of MDMA use similarly extreme procedures – giving monkeys the equivalent of 50 pills over three days, for example. Although this demonstrates that MDMA can be harmful, the implications for ‘normal’ drug use among humans are not clear. Other research, published today, but not mentioned in the Guardian article until towards the end, suggest that the side-effects of ecstasy use are temporary. The research mentioned failed to find a significant difference between users and non-users in either amount of depression or in neuroanatomical differences revealed by brain scans. But this can’t prove that there’s isn’t an effect (because absence of evidence isn’t evidence of absence). The man was also a heavy cannabis user (and probably other things too), although this also isn’t mentioned until the end of the article. It is hard to be sure which drug(s) caused his problems. Finally, what kind of man would take 40,000 ecstasy pills?! His psychological and, potentially neurological, make-up was probably unusual before he went anywhere near the E
Link: ‘The strange case of the man who took 40,000 ecstasy pills in nine years’ (The Guardian)
Link: Erowid.org pages on MDMA
Mind Hacks 
I have a major issue with “The research mentioned failed to find a significant difference between users and non-users in either amount of depression or in neuroanatomical differences revealed by brain scans. But this can’t prove that there’s isn’t an effect (because absence of evidence isn’t evidence of absence).”
This is a fundamental misunderstanding of the nature of evidence. The “absence of evidence isn’t evidence of absence” motto has been taken up by the anti-science crowd and hugely misapplied.
A study which shows no difference between two groups *is* evidence. No single scientific study is proof, but certainly this study refutes the premise “those who use ecstasy suffer from noticeably increased levels of depressions and other neuroanatomical changes”. The “absence of evidence” argument can be applied not when the evidence is negative (as in this case), but rather when something hasn’t been studied at all. For example, consider the contention that religion causes cancer (intentially silly example). I expect that you can’t refute this, because there are no significant studies on statistical correlations—there is an absence of evidence. But if you then did perform a large statistical study which showed the cancer rate to be identical (controlling for other known factors) among the religious and the non-religious, you *would* now have evidence that religion does *not* cause cancer.
This “you can’t prove a negative” meme simply misinterprets science: science doesn’t prove positives; it collects evidence to refute theories. The simplest theory available which makes useful predictions but which hasn’t been significantly refuted receives the moniker “scientific truth”. This doesn’t really tell you what is “objectively true”, but science is really good at telling you what is false, and that’s often what people mean by “proving a negative”.
One thing I did not see mentioned anywhere is how certain they are that the substance was indeed pure MDMA. “Exstacy” and MDMA are no longer interchangable. I find it hard to believe that a party user who is doing that many pills is aware of his source. The pills could have anything in them, such as Methamphetamine. It seems that they were going by the word of Mr.A. Many people think that what they take is pure, when in really isn’t.
Knigel – good point; it’s another difficulty which weakens the possible conclusions from this kind of research
Rob – absolutely, and thanks for correcting me. By quoting the “absence of evidence isn’t evidence of absence” motto I meant that the inference from a study which shows no evidence of harm is less strong than a study which does show a positive effect (although it may be more relevant, as in this case). Perhaps the drug isn’t harmful in low doses, perhaps the study wasn’t powerful enough. How can we know? Obviously a series of well-designed studies can allow us to be more confident in the conclusion that the absence of evidence is of absence, but surely there remains a tendency for this kind of result to be less conclusive? Or have i read you wrong?
What kind of man indeed?
Researchers in Hong Kong (James Yip and colleagues) conducted extensive neuropsychological testing in large numbers of abstinent ecstasy users (n=100), and found impairments on verbal and non-verbal memory, complex attention, and verbal fluency. However, the abstinent ecstasy users performed *better* on figural fluency relative to their non-user counterparts (more “creative” at generating abstract figures, dude!). But basically, cognitive performance does not look good after taking 4 tablets per week for 2-3 months, even after abstaining for at least 1 month!
Yip JT, Lee TM. (2005) Effect of ecstasy use on neuropsychological function: a study in Hong Kong.
Psychopharmacology 179(3):620-8.
Other than the large sample size, the reason this particular Hong Kong population is so interesting is that the individuals did not drink or use any drugs other than MDMA (no cannabis, not even nicotine). Users and non-users were recruited from the same rave parties and clubs.