"the only reason i gave concerta a 2 and not a 0, was because when i didn&#039;t take it for two days i could feel myself going through a withdrawal. i would begin to feel tired, annoyed and angered easily, some headaches, and so on. i have been on concerta for about 13 years and even with it in my system i still struggled in school. at first they had me on smaller doses, but they had to be increased. i&#039;ve been taking 108mg each morning and the only thing that i have noticed a difference in is the withdrawal i go through, which can be helped by drinking coffee. by the way, i&#039;m currently on the drug right now and i&#039;m supposed to be studying for my spanish exam that i have this afternoon. so if that doesn&#039;t tell you something then idk what will."