https://en.wikipedia.org/wiki/MPTP
There is so much to learn from these things, the cure for natural parkison's is probably within that drug, but we need the whole supply chain regulated and the ability to study these things in the light.
I absolutely hate the current status of the psychedelic community, full of anecdotes, invalidating victim's experiences, some straight up voodoo about how to "end trips early" with candy flipping. Dangerous. All because it relies on urban legends.
The proper way to do it is to use a drug that's a 5-HT2a antagonist with a stronger affinity to that receptor than the psychedelic. Trazodone or Seroquel are commonly prescribed ones that have a pretty low side effect profile and can be found at any pharmacy.
I wish there was more advocacy around this. DanceSafe [1] sells inexpensive kits that people can use to test against most of the bad stuff (like NBOMEs).
https://www.justice.gov/usao-ut/pr/shamo-sentenced-life-pris...
Also another second hand anecdote, most coke you buy in America or Canada is probably not pure. Even when getting supposedly pure coke. I've heard what they have in south america and mexico in certain places is nothing like what they have up here.
No speediness, you can sleep, no cravings or come down.
Kidding aside, I'm not sure what margins they are running on. I can't imagine they are selling enough kits that lowering the price wouldn't it make it impossible for them to exist.