tegretol - carbamazepine - my friend developed brain damage on it.

Amazingly someone else on reddit noticed something similar, it can really damage your personality.

https://www.reddit.com/r/BipolarReddit/comments/wbig6f/warning_on_tegretol_gave_my_relative_deep_mental/

My friend developed what I can only describe as deep anger, hatred and afrustration of other people. He would begin regularly mumbling to himself, no awareness of surroundings. It really affected his empathy levels, he would just dismiss people and couldn't be bothered to interact with them. I have no idea what this medication does to the brain, but it isn't nice at all. It really turns you into a nasty person to be around.