What is ADHD?

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ADHD is one of the most common neurodevelopmental disorders of childhood. It is usually first diagnosed in childhood and often lasts into adulthood. Children with ADHD may have trouble paying attention, controlling impulsive behaviors (may act without thinking about what the result will be), or be overly active.

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Signs and Symptoms

It is normal for children to have trouble focusing and behaving at one time or another. However, children with ADHD do not just grow out of these behaviors. The symptoms continue, can be severe, and can cause difficulty at school, at home, or with friends.

A child with ADHD might:

daydream a lot
forget or lose things a lot
squirm or fidget
talk too much
make careless mistakes or take unnecessary risks
have a hard time resisting temptation
have trouble taking turns
have difficulty getting along with others

Learn more about signs and symptoms

Types

There are three different types of ADHD, depending on which types of symptoms are strongest in the individual:

ADHD Fact Sheet

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Predominantly Inattentive Presentation: It is hard for the individual to organize or finish a task, to pay attention to details, or to follow instructions or conversations. The person is easily distracted or forgets details of daily routines.

Predominantly Hyperactive-Impulsive Presentation: The person fidgets and talks a lot. It is hard to sit still for long (e.g., for a meal or while doing homework). Smaller children may run, jump or climb constantly. The individual feels restless and has trouble with impulsivity. Someone who is impulsive may interrupt others a lot, grab things from people, or speak at inappropriate times. It is hard for the person to wait their turn or listen to directions. A person with impulsiveness may have more accidents and injuries than others.

Combined Presentation: Symptoms of the above two types are equally present in the person.

Because symptoms can change over time, the presentation may change over time as well.

Causes of ADHD

Scientists are studying cause(s) and risk factors in an effort to find better ways to manage and reduce the chances of a person having ADHD. The cause(s) and risk factors for ADHD are unknown, but current research shows that genetics plays an important role. Recent studies of twins link genes with ADHD.1

In addition to genetics, scientists are studying other possible causes and risk factors including:

Brain injury
Exposure to environmental (e.g., lead) during pregnancy or at a young age
Alcohol and tobacco use during pregnancy
Premature delivery
Low birth weight

Research does not support the popularly held views that ADHD is caused by eating too much sugar, watching too much television, parenting, or social and environmental factors such as poverty or family chaos. Of course, many things, including these, might make symptoms worse, especially in certain people. But the evidence is not strong enough to conclude that they are the main causes of ADHD.

Diagnosis

Deciding if a child has ADHD is a process with several steps. There is no single test to diagnose ADHD, and many other problems, like anxiety, depression, sleep problems, and certain types of learning disabilities, can have similar symptoms. One step of the process involves having a medical exam, including hearing and vision tests, to rule out other problems with symptoms like ADHD. Diagnosing ADHD usually includes a checklist for rating ADHD symptoms and taking a history of the child from parents, teachers, and sometimes, the child.

Learn more about the criteria for diagnosing ADHD

Treatments

In most cases, ADHD is best treated with a combination of behavior therapy and medication. For preschool-aged children (4-5 years of age) with ADHD, behavior therapy, particularly training for parents, is recommended as the first line of treatment before medication is tried. What works best can depend on the child and family. Good treatment plans will include close monitoring, follow-ups, and making changes, if needed, along the way.

Learn more about treatments

Managing Symptoms: Staying Healthy

Being healthy is important for all children and can be especially important for children with ADHD. In addition to behavioral therapy and medication, having a healthy lifestyle can make it easier for your child to deal with ADHD symptoms. Here are some healthy behaviors that may help:

Developing healthy eating habits such as eating plenty of fruits, vegetables, and whole grains and choosing lean protein sources
Participating in daily physical activity based on age
Limiting the amount of daily screen time from TVs, computers, phones, and other electronics
Getting the recommended amount of sleep each night based on age

Get Help!

If you or your doctor has concerns about ADHD, you can take your child to a specialist such as a child psychologist or developmental pediatrician, or you can contact your local early intervention agency (for children under 3) or public school (for children 3 and older).

The Centers for Disease Control and Prevention (CDC) funds the National Resource Center on ADHD, a program of CHADD – Children and Adults with Attention-Deficit/Hyperactivity Disorder. Their website has links to information for people with ADHD and their families. The National Resource Center operates a call center (1-800-233-4050) with trained staff to answer questions about ADHD.

For more information on services for children with special needs, visit the Center for Parent Information and Resources. To find the Parent Center near you, you can visit this website.

ADHD in Adults

ADHD can last into adulthood. Some adults have ADHD but have never been diagnosed. The symptoms can cause difficulty at work, at home, or with relationships. Symptoms may look different at older ages, for example, hyperactivity may appear as extreme restlessness. Symptoms can become more severe when the demands of adulthood increase. For more information about diagnosis and treatment throughout the lifespan, please visit the websites of the National Resource Center on ADHD and the National Institutes of Mental Health.