NIH - Attention Deficit Hyperactivity Disorder

"According to the most recent version of the Diagnostic and Statistical Manual of Mental Disorders2 (DSM-IV-TR), there are three patterns of behavior that indicate ADHD. People with ADHD may show several signs of being consistently inattentive. They may have a pattern of being hyperactive and impulsive far more than others of their age. Or they may show all three types of behavior. This means that there are three subtypes of ADHD recognized by professionals. These are the predominantly hyperactive-impulsive type (that does not show significant inattention); the predominantly inattentive type (that does not show significant hyperactive-impulsive behavior) sometimes called ADD—an outdated term for this entire disorder; and the combined type (that displays both inattentive and hyperactive-impulsive symptoms)."

Highlighted Article

[The addictive potential of methylphenidate.] (Psychiatr Prax. 2007)

"CONCLUSIONS According to the "experienced" drug users, there is a mild to moderate abuse potential of methylphenidate. However, its effects are not comparable with amphetamine or cocaine.)."