Attention deficit hyperactivity disorder (ADHD) is a psychological problem that presents itself as a persistent pattern of inattentiveness, over-activity, impulsivity, or a combination of these behaviors. For many children, some degree of fidgetiness, inattentiveness and impulsivity is appropriate. Therefore, for these problems to be diagnosed as ADHD, they must be out of the normal range for a child’s age and development. ADHD is the most commonly diagnosed behavioral disorder of childhood and it affects about 3–5% of school aged children.