I would also not suggest doing it alone, but that is true for pretty much any hallucinogen. And when I say don't do it alone I don't mean do it with other people, I mean have a sober person with you. You can be so altered that you could kill yourself and not even realize what you are doing.
As experience being the sober person, that can actually be a bit scary. When you friend is tripping balls. 90% of the time it's just really funny.
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