ADHD: what is it?

Patients with attention-deficit hyperactivity disorder (ADHD) have difficulty with hyperactivity, impulsivity, and inattention. ADHD was first described as a medical disorder in 1910, but there are descriptions of ADHD even in ancient texts. In 1935 it was described that children who suffered from ADHD showed a robust response to stimulant medication, and since that time stimulant medication has been a cornerstone of treatment. ADHD is not a modern fad. It is not caused by bad parents, bad teachers, or poor discipline. Individuals with ADHD do not misbehave on purpose or to spite others. They often do not know why they do the things that get them into trouble.

There are 3 subtypes of ADHD: the inattentive type (problems with attention), the hyperactive-impulsive type (problems with hyperactive and impulsive behaviours), and the combined type (problems in both areas). The subtypes seem to have some relationship to age and gender. Preschoolers are more likely to have difficulty with being hyperactive and impulsive. The inattentive type of ADHD is more prevalent in girls than other types of ADHD. Since overt hyperactive behaviours diminish with age, more adults have attention problems than symptoms of hyperactivity. There seem to be some children who meet the criteria for the inattentive type, who have a distinct set of difficulties, quite different to the combined type. These children have problems learning in school, and are often sluggish and dreamy. They are less likely to have behaviour problems.