everyone is different, my first time ever trying stimulant based medication, was by a doctor,. I was given Ritalin 20mg SR, and it made me euphoric and it def made me feel like I was on a recreational dose, that's how my addiction started. while I met other people who can take a 30mg of Adderall and never have touched amphetamines and get no effect..body weight plays no role in dose, its all your brain chemistry