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:
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.
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.