I took a fair amount of the stuff back in the 1980s -- at one point I estimated my cumulative total consumption as around 15 grams. (I'm sure there are people far beyond that now.)
It is definitely neurotoxic -- I could tell that the first time I took it -- but in my experience, the noticeable effects are temporary, being mostly gone in a couple of weeks and quite undetectable after a couple of months. As a software developer who works in a fairly technical field, I'm quite sensitive to how well my brain is working on any given day. I did not notice any long-term falloff in my abilities as a result of MDMA use.
All that said -- it does invite abuse, and I was abusing it. In 1990, my then-SO left me, and I realized I had to quit.
I wouldn't worry about occasional, supervised, therapeutic MDMA use by healthy individuals.
I used a lot of MDMA 20+ years ago. I was immediately aware, on trying it, that it was neurotoxic. I don't know how I knew that, but I did. However, after I quit I saw no evidence of permanent damage. As a fairly high-level software developer, I'm pretty sensitive to the state of my brain, and I don't recall ever experiencing difficulty working more than 2 or 3 weeks after taking MDMA.
Also, I only heard about this right before I quit, but a lot of the toxicity can be averted by taking 20mg of fluoxetine 3 to 4 hours into the experience. (It diminishes the drug effect, so you don't want to take it too soon.) The theory I heard is that MDMA or, more likely, one of its metabolites, binds to serotonin receptors and damages them. Taking something else that binds to the receptors, then, can help protect them. I tried it once and it seemed to help. St. John's Wort might work too, and is easier to get.
All that said -- I agree that people should be more careful with it. It's a potent psychoactive drug that's harder on the body than most of them, dehydration being a real risk.
It is definitely neurotoxic -- I could tell that the first time I took it -- but in my experience, the noticeable effects are temporary, being mostly gone in a couple of weeks and quite undetectable after a couple of months. As a software developer who works in a fairly technical field, I'm quite sensitive to how well my brain is working on any given day. I did not notice any long-term falloff in my abilities as a result of MDMA use.
All that said -- it does invite abuse, and I was abusing it. In 1990, my then-SO left me, and I realized I had to quit.
I wouldn't worry about occasional, supervised, therapeutic MDMA use by healthy individuals.