These folks have been documenting the causal link between psychotropic drugs and incidents of extreme violence for years now:
There are also new studies that link early heavy marijuana use to schizophrenia. We have had several instances in our county of murder by a mentally ill person who had been an early marijuana user.
We had a sixteen year old who flipped out and strangled a 350 pound woman and after carrying her up a ladder to her loft. I think that he must have stabbed her first and then strangled her with the vacuum cord after he got her up into the loft. Somehow the kid developed super powers while in a psychotic state. He was just a skinny medium height 16 year old.
We had another guy whose mental illness was attributed to early drug use, who went on a rampage and murdered all his neighbors and then stole one of their trucks and drove to a gas station where he killed a police officer and shot someone else.
Then there was the local guy who went off his meds because people told him that medical marijuana would work just as well. He took his mother and sister hostage and then when the father came in and tried to free them, he shot and killed his own father.
…and those are just the first three that I can think of.
Oh, I don’t know how I could leave this out. My son-in-laws brother is schizophrenic and the doctors also contribute that to early drug use (mostly marijuana) in high school and college. He hears voices and has tried to kill his mother several times.