How much do you weigh? If you weigh from 100-150.. don't take more than 40 mg of Adderall your first couple of times or you may have a bad come down. You will feel great for about 7-8 hours. If you weigh 150+ you can take about 60-75 mg in a short while, but take 54 your first couple of times.

Don't take Ritalin. Same medicine, but comedowns are more frequent on people who pop Ritalin instead of Add.