What is attention deficit hyperactivity disorder?

Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood disorders and can continue through adolescence and adulthood. Symptoms include difficulty staying focused and paying attention, difficulty controlling behavior, and hyperactivity (over-activity).

ADHD has three subtypes:¹

• Predominantly hyperactive-impulsive
  • Most symptoms (six or more) are in the hyperactivity-impulsivity categories.
  • Fewer than six symptoms of inattention are present, although inattention may still be present to some degree.

• Predominantly inattentive
  • The majority of symptoms (six or more) are in the inattention category and fewer than six symptoms of hyperactivity-impulsivity are present, although hyperactivity-impulsivity may still be present to some degree.
  • Children with this subtype are less likely to act out or have difficulties getting along with other children. They may sit quietly, but they are not paying attention to what they are doing. Therefore, the child may be overlooked, and parents and teachers may not notice that he or she has ADHD.

• Combined hyperactive-impulsive and inattentive
  • Six or more symptoms of inattention and six or more symptoms of hyperactivity-impulsivity are present.
  • Most children have the combined type of ADHD.

Treatments can relieve many of the disorder’s symptoms, but there is no cure. With treatment, most people with ADHD can be successful in school and lead productive lives. Researchers are developing more effective treatments and interventions, and using new tools such as brain imaging, to better understand ADHD and to find more effective ways to treat and prevent it.