Not to be mean, but that sounds horrible. I would never want to be under that influence, or experience stuff like that. Even if a certain drug "helps me focus (?????)" I would never do that because your body is still being put under an influence, doesn't matter if it's "harmful" or not.

I don't care who you are: best friend, girlfriend, cousin, person from school, or even my own dad, if you offer me any type of drug or try to pressure me into doing something, then goodbye I am never interacting with you again until you get something in your life straightened out.

Maybe I could accept having a friend who does that. Of course I wouldn't be happy with it and I would try to convince them to stop doing it as soon as possible. But I will leave if someone tries to pressure me into doing a drug that I don't want to do.