It's well known that drug use is linked to serious chronic mental illness.
30 years ago, I had a close friend who went on a honeymoon w her new guy to Mexico and hit the shrooms and peyote pretty hard. She went into full manic and remained bipolar for the rest of her life. Frequent hospitalizations. Lithium therapy. And then eventually, not even that would keep her together and she ended up being permanently resident at CAMH.
Drug use can also provoke temporary insanity. An escort regular / friend of mine went insane for about a week a couple years ago after using a new, sketchy batch of street fentanyl. Another escort friend of mine went insane for about a month back in 2009 after a massive coke binge. Both came back to normal.