I should qualify myself here - we are adults ------and any substance can be a poison.
For instance you can probably remember a runner or two who after a full marathon has been so dehydrated they drank and drank more and more water.
And then they died. They died because they fantastically altered their brain chemistry.
Further there are stories along these lines of those in mental hospitals hanging out in hospital washrooms drinking and drinking water
---- why ??? To get high !!! Any substance taken in large amounts --- food, sugar---nicotine - WATER-- can under the right conditions can really mess you up.
I posted this to show that there is evidence that these "trips" that people take (taken under medical supervision) take you some where. This somewhere can be scary or revealing and can be life altering. Where you go is open to debate. But I find it intriguing and it opens a huge number of questions.
If you go on Joe Rogan you can hear him talking about it if it interests you.
There is a big push now for those studying the mind and addictive behaviours and those who are habitual criminals and so on who are now supporting a drive to study these substances because reports are saying that very big changes are being seen in peoples behaviours for the positive when they are (under medical supervision) given the active agent of the right sort of mushroom.
What it seems to do is take you to similar places that those who have NDE near death experiences ( they are very different) but sort of similar. And the person who is a thief, criminal, abuser, and so on is offten changed so much so that they start doing better things, stop smoking, getting jobs, stop stealing and so on.
I read about most every sort o f subject and look at it as science o f some type. Maybe the topic is of interest.
Paul Stamets is the name to google.