Although it has taken quite some time for our society to accept ADHD or Attention Deficit Hyperactivity Disorder as a bonafide mental health and/or medical disorder, in actuality it is a problem that has been noted in modern literature for at least 200 years. As early as 1798, ADHD was first described in the medical literature by Dr. Alexander Crichton, who referred to it as "Mental Restlessness."  

Although it has taken quite some time for our society to accept ADHD or Attention Deficit Hyperactivity Disorder as a bonafide mental health and/or medical disorder, in actuality it is a problem that has been noted in modern literature for at least 200 years. As early as 1798, ADHD was first described in the medical literature by Dr. Alexander Crichton, who referred to it as "Mental Restlessness."  A fairy tale of an apparent ADHD youth, "The Story of Fidgety Philip," was written in 1845 by Dr. Heinrich Hoffman. In 1922, ADHD was recognized as Post Encephalitic Behavior Disorder. In 1937 it was discovered that stimulants helped control hyperactivity in children. In 1957 methylphenidate (Ritalin), became commercially available to treat hyperactive children.  

The formal and accepted mental health/behavioral diagnosis of ADHD is relatively recent. In the early 1960s, ADHD was referred to as "Minimal Brain Dysfunction." In 1968, the disorder became known as "Hyperkinetic Reaction of Childhood." At this point, emphasis was placed more on the hyperactivity than inattention symptoms. In 1980, the diagnosis was changed to "ADD--Attention Deficit Disorder, with or without Hyperactivity," which placed equal emphasis on hyperactivity and inattention. By 1987, the disorder was renamed Attention Deficit Hyperactivity Disorder (ADHD) and was subdivided into four categories (see below). Since then, ADHD has been considered a medical disorder that results in behavioral problems.  

Currently, ADHD is defined by the DSM IV-TR (the accepted diagnostic manual) as one disorder which is subdivided into four categories:  

1. Attention-Deficit/Hyperactivity Disorder, Predominantly Inattentive Type  (previously known as ADD) is marked by impaired attention and concentration.  

2. Attention-Deficit/Hyperactivity Disorder, Predominantly Hyperactive, Impulsive Type (formerly known as ADHD) is marked by hyperactivity without  inattentiveness.  

 3. Attention-Deficit/Hyperactivity Disorder, Combined Type (the most common type) involves all the symptoms: inattention, hyperactivity, and impulsivity.