How many days should I give a dose of adderall to know if it is really working? I posted early saying I was put on 10mg of generic Adderall 2 times a day. Saturday (my second day) I thought I could really feel it working because I was really able to focus on my homework but not for long periods of time. Later I remeber I drank coffee that morning forgetting that it probably wasn't a good idea. So I think the coffee made it seem a little different, because sunday morning I took 10mg without coffee or ther caffine and I didn't seem exactely the same. SO I tried 20mg on sunday afternoon, it seemed like I was able to focus better.I am not sure if I am giving the 10mg enough time to see if it is really working. I didn't have any bad with the 20mg so I don't think it is too much. I am planning on taking 20mg 2X today, hopefully in class I will be able to notice more of a difference.