i've noticed that lately alot of people i know have been taking adderall [non-presribed.. they get it from other people]. and i didnt think much of it because i wouldnt never take anyone elses drugs, and wouldnt take any unless prescribed directly to me. but one of my friends took 30mg last night [her first time, and last time trying it she sweared], and freaked out. she said she couldnt stop shaking and her heart was beating fast, she couldnt eat or sleep. i'm glad she's okay, now, but she's still feeling a little sick today. i know adderall is used to treat ADD, and things like that. but what happens to your body when you take it? why do people take it if it isnt prescribed?