Attention-Deficit Hyperactivity Disorder (ADHD)

What Is It?

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder (a problem related to brain development) that causes hyperactivity (always on the move), impulsive behavior (doing things without any self control), and attention problems (not able to pay attention). ADHD is the most common problem encountered in outpatient child and adolescent mental health settings. It is estimated that ADHD affects between 4 percent and 12 percent of school-aged children, more often boys than girls. Studies suggest that the amount of ADHD seen in the population has risen significantly in recent years. This is partly because of an increased awareness and recognition of the disorder, and partly because the specific things needed to make the diagnosis of ADHD have been more clearly defined during the past 20 years.




Parents of a child who has ADHD may receive a note from school saying that their child “won’t listen to the teacher,” “is too active or hyper,” or “causes trouble in class and is disruptive.” Even though a child with ADHD often wants to be a good student, his or her impulsive behavior and inability to pay attention in class make it difficult. Teachers, parents and friends may see that the child is “misbehaving” or acting “different,” but they might not be able to tell exactly what is wrong.

Over the years there have been changes in what are considered to be the essential symptoms of ADHD. In general, children with ADHD have a hard time with normal activities of everyday life because of significant problems with inattention, hyperactivity and/or impulsive behavior. Unlike the normally high level of activity sometimes seen in children who do not have ADHD, the hyperactivity of ADHD happens more often and is typically more haphazard, poorly organized and not goal directed (have no real purpose). Likewise, children who do not have ADHD occasionally are impulsive or inattentive. In children with ADHD, these behaviors are so frequent that they make it hard for the child to learn in school, get along with others or be safe.

Although specific symptoms of ADHD vary from child to child, a child with ADHD generally shows several of the following characteristics:

  • Difficulty organizing work, often giving the impression of not having heard the teacher’s instructions
  • Easily distracted
  • Excessively restless or fidgety behavior; unable to stay seated
  • Impulsive behavior (acts without thinking)
  • Carelessness
  • Frequently calling out in class (without raising hand, yelling out answer before question is finished)
  • Failing to follow through with teachers’ or parents’ requests
  • Difficulty waiting for his or her turn in group settings
  • Unable to stay focused on a game, project or homework assignment; often moving from one activity to the next without completing any

In addition to the characteristics listed above, many children with ADHD also show symptoms of other behavioral or psychiatric conditions. These associated conditions include learning disabilities and disorders characterized by disruptive behavior.

  • Learning disabilities — Studies have shown that at least 20 percent of children with ADHD also have learning disabilities. This is many times greater than the rate seen in the general population. Problems related to the child’s learning disability may lead to increased levels of anger and frustration.

  • Oppositional defiant or conduct disorders — These behavior disorders affect about one-third of all children who have ADHD. Studies have shown that children who have both ADHD and behavioral disturbances have an increased risk of having a poor long-term outcome, with a higher incidence of school failure, antisocial behaviors and substance abuse.


There is no single test to diagnose ADHD. Your doctor may make the diagnosis and/or may refer your child to a specialist, if necessary. The doctor will ask you if your child has shown any of the characteristics of ADHD. Since many of these characteristics are more likely to be seen in a school setting, your doctor also will ask about your child’s behavior in school. To help collect this information, parents, teachers and other caregivers may be asked to fill out special behavioral checklists.

Your pediatrician also will ask about your child’s medical and developmental history, and will do a physical examination. It is important to be sure that your child does not have other conditions that may affect his or her behavior, such as trouble hearing or seeing, learning disabilities, speech problems, seizure disorders, anxiety, depression or other behavior problems. In some cases, psychological and neuropsychological testing is necessary to assess intelligence and academic potential.

Expected Duration

In most children with ADHD, symptoms begin before age 7 and persist through adolescence. In some cases, symptoms continue into adulthood


Despite years of research, the exact cause of ADHD is still not fully understood. There are numerous factors, alone or in combination, that may contribute to the development of ADHD in a child. These include:

  • Genetic factors
  • History of Head injury
  • Infections of the brain and spinal cord
  • Premature birth
  • Exposure to tobacco, alcohol or other drugs while in the womb
  • Lead poisoning


Although there is no cure for ADHD, many treatment options are available. The goal of treatment is to help children improve social relationships, do better in school, and keep their disruptive and dangerous behaviors to a minimum. Medication alone rarely is the answer. The best results usually are achieved with a combination of medication and behavior therapy.

Several different types of medication are prescribed by doctors to treat ADHD. Stimulants, such as methylphenidate (Ritalin, Concerta and others) and forms of amphetamine (Dexedrine, Adderall and others) are safe and effective for most children, helping them to focus their thoughts and control their behavior. Despite their name, stimulants do not cause increased hyperactivity or impulsivity. In some children, these medications may cause mild side effects, such as decreased appetite, weight loss, stomachaches, sleep problems, headaches and jitteriness. Rarely, more serious side effects may occur, such as dizziness, stuttering, tics or increased blood pressure. Children who take stimulants should be monitored regularly to make sure that the medication is working properly and to check for side effects.

Other treatment approaches, used alone or in combination, may include:

  • Behavioral therapy — This refers to techniques that try to improve behavior, usually by rewarding and encouraging desirable behaviors and by discouraging unwanted behaviors and pointing out the consequences.
  • Cognitive therapy — This is psychotherapy designed to help a child change his or her thinking so that he or she can build self esteem, stop having negative thoughts, and improve problem solving skills.
  • Social skill training — Improving social skills helps children with ADHD to make and keep friends.
  • Parent education and support — Training classes, support groups, and counselors can help to teach and support parents about ADHD, including strategies for dealing with ADHD related behaviors.

Because many children with ADHD also are troubled by poor grades and school behavior problems, it is important that schools provide educational adjustments and interventions (such as an individualized educational plan) to promote the best possible learning environment for the child.

When To Call A Professional

Call your doctor if your child shows symptoms of ADHD, or if teachers notify you that your child is having academic difficulties, behavioral problems or difficulty paying attention.


ADHD can cause significant emotional, social and educational problems. However, when ADHD is diagnosed early and treated properly, the condition can be managed effectively, so children can grow up to have productive, successful and fulfilling lives. Although some children appear to grow out of their ADHD as they reach their adolescent years, others have lifelong symptoms.


Johns Hopkins patient information

Last revised: December 3, 2012
by Gevorg A. Poghosian, Ph.D.

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