Is ADHD Classified as a Mental Illness?

Yes. Attention deficit hyperactivity disorder (ADHD) refers to a chronic biobehavioral disorder that initially manifests in childhood and is characterized by problems of hyperactivity, impulsivity, and/or inattention.

Not all affected individuals manifest all three behavioral categories. These symptoms have been associated with difficulty in academic, emotional, and social functioning. The diagnosis is established by satisfying specific criteria outlined in the DSM-V, the diagnostic manual for the psychiatry and psychology field.

The condition may be associated with other neurological conditions, significant behavioral problems (for example, oppositional defiant disorder), and/or developmental/learning disabilities. Therapeutic options included the use of medication, behavioral therapy, and adjustments in day-to-day lifestyle activities. People with ADHD are much more likely than the general population to have other related conditions such as learning disorders, restless legs syndrome, ophthalmic convergence insufficiency, depression, anxiety disorder, antisocial personality disorder, substance abuse disorder, conduct disorder, and obsessive-compulsive behavior. People with ADHD are also more likely than the general population to have a family member with ADHD or one of the related conditions.

ADHD is one of the more common disorders of childhood. Studies in the United States indicate that approximately 8%-10% of children satisfy the diagnostic criteria for ADHD. ADHD occurs two to four times more commonly in boys than girls (male to female ratio 4:1 for the predominantly hyperactive type versus 2:1 for the predominantly inattentive type). While previously believed to be "outgrown" by adulthood, current opinion indicates that many children will continue throughout life with symptoms that may affect both occupational and social functioning. Some medical researchers note that approximately 40%-50% of ADHD-hyperactive children will have (typically non-hyperactive) symptoms that persist into adulthood.

The medical community recognizes three basic forms of the disorder:

• Primarily inattentive: recurrent inattentiveness and inability to maintain focus on tasks or activities. In the classroom, this may be the child who is "spacing out" and "can't stay on track."
• Primarily hyperactive-impulsive: Impulsive behaviors and inappropriate movement (fidgeting, inability to keep still) or restlessness are the primary problems. Unlike the inattentive ADHD-type child, this individual is more often the "class clown" or "class devil" -- either manifestation leads to recurrent disruptive problems.
• Combined: This is a combination of the inattentive and hyperactive-impulsive forms.

The combined type of ADHD is the most common. The predominantly inattentive type is being recognized more and more, especially in girls and in adults. The predominantly hyperactive-impulsive type, without significant attention problems, is rare.

We are still learning about ADHD, and experts' understanding of the disorder is still being refined.

For more information, please see our slideshow about symptoms of ADHD in children