was diagnosed with adhd about 2 mos ago and my doctor put me on 36mgs of concerta it seems to help with the impulse control, but I am still having an issue with my mind being in a thousand different places. I also have a seven year old son who was also diagnosed with adhd about a week ago and because of his size he is also on 36mg of concerta and it is making him calmer at home, but when I talked to his teacher today she said that she is not seeing any improvement at all. How long does it take this medication to stat working completely?