When a hyperactive person takes Adderall it is supposed to mellow them out, not make them slow, just calm them down enough so that they can concentrate and focus on things. It is a drug for people that suffer from ADHD. If you are taking this drug and it is making you feel dopey, you need to talk to your doctor and have him adjust the dosage.
Adderall has the same effect on a person without ADD or ADHD that sped has on a "normal" person. It makes you focus extremely hard on certain things and gives you a ton of energy. I DO NOT RECOMMEND YOU TAKE ANYTHING NOT PRESCRIBED TO YOU BY A DOCTOR!