What Matt didn't realize-until much later-was that (drug use) only exacerbated his problems. He says, "As soon as I was off whatever I was on, my problems were 50 times worse and I couldn't control myself. I'd get sad and agitated. I went off on people. I busted holes in walls. I still have a door in my closet that I literally punched through everywhere but the corners. I just sat there and beat up my door because I hated myself. That's why I wanted to be high all the time."
Source: www.abovetheinfluence.com
Chronic use of some drugs of abuse can cause long-lasting changes in the brain, which may lead to paranoia, depression, aggression, and hallucinations.