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:

• 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.

What are the symptoms of ADHD in children?

Inattention, hyperactivity, and impulsivity are the key behaviors of ADHD. It is normal for all children to be inattentive, hyperactive, or impulsive sometimes, but for children with ADHD, these behaviors are more severe and occur more often. To be diagnosed with the disorder, a child must have symptoms for 6 or more months and to a degree that is greater than other children of the same age.

Children who have symptoms of inattention may:

• Be easily distracted, miss details, forget things, and frequently switch from one activity to another
• Have difficulty focusing on one thing
• Become bored with a task after only a few minutes, unless they are doing something enjoyable
• Have difficulty focusing attention on organizing and completing a task or learning something new
• Have trouble completing or turning in homework assignments, often losing things (e.g., pencils, toys, assignments) needed to complete tasks or activities
• Not seem to listen when spoken to
• Daydream, become easily confused, and move slowly
• Have difficulty processing information as quickly and accurately as others
• Struggle to follow instructions.

Children who have symptoms of hyperactivity may:

• Fidget and squirm in their seats
• Talk nonstop
• Dash around, touching or playing with anything and everything in sight
• Have trouble sitting still during dinner, school, and story time
• Be constantly in motion
• Have difficulty doing quiet tasks or activities.

Children who have symptoms of impulsivity may:

• Be very impatient
• Blurt out inappropriate comments, show their emotions without restraint, and act without regard for consequences
• Have difficulty waiting for things they want or waiting their turns in games
• Often interrupt conversations or others' activities.

ADHD Can Be Mistaken for Other Problems

Parents and teachers can miss the fact that children with symptoms of inattention have the disorder because they are often quiet and less likely to act out. They may sit quietly, seeming to work, but they are often not paying attention to what they are doing. They may get along well with other children, compared with those with the other subtypes, who tend to have social problems. But children with the inattentive kind of ADHD are not the only ones whose disorders can be missed. For example, adults may think that children with the hyperactive and impulsive subtypes just have emotional or disciplinary problems.

What conditions can coexist with ADHD?

Some children with ADHD also have other illnesses or conditions. For example, they may have one or more of the following:

• A learning disability. A child in preschool with a learning disability may have difficulty understanding certain sounds or words or have problems expressing himself or herself in words. A school-aged child may struggle with reading, spelling, writing, and math.

Oppositional defiant disorder. Kids with this condition, in which a child is overly stubborn or rebellious, often argue with adults and refuse to obey rules.

• Conduct disorder. This condition includes behaviors in which the child may lie, steal, fight, or bully others. He or she may destroy property, break into homes, or carry or use weapons. These children or teens are also at a higher risk of using illegal substances. Kids with conduct disorder are at risk of getting into trouble at school or with the police.

• Anxiety and depression. Treating ADHD may help to decrease anxiety or some forms of depression.

• Bipolar disorder. Some children with ADHD may also have this condition in which extreme mood swings go from mania (an extremely high elevated mood) to depression in short periods of time.

• Tourette syndrome. Very few children have this brain disorder, but among those who do, many also have ADHD. Some people with Tourette syndrome have nervous tics and repetitive mannerisms, such as eye blinks, facial twitches, or grimacing. Others clear their throats, snort, or sniff frequently, or bark out words inappropriately. These behaviors can be controlled with medication.

ADHD also may coexist with a sleep disorder, bed-wetting, substance abuse, or other disorders or illnesses.