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Attention-deficit hyperactivity disorder (ADHD)

Medically reviewed by Last updated on Mar 11, 2024.

What is attention-deficit hyperactivity disorder (ADHD)?

Harvard Health Publishing

Attention-deficit hyperactivity disorder (ADHD), usually first diagnosed in childhood, can appear in a variety of forms and has many possible causes. People with ADHD probably have an underlying genetic vulnerability to developing it, but the severity of the problem is also influenced by the environment. Conflict and stress tend to make it worse.

The main features of this disorder are found in its name. Attention problems include daydreaming, difficulty focusing and being easily distracted. Hyperactivity refers to fidgeting or restlessness. A person with the disorder may be disruptive or impulsive, may have trouble in relationships and may be accident-prone. Hyperactivity and impulsiveness often improve as a person matures, but attention problems tend to last into adulthood.

ADHD is the most common problem seen in outpatient child and adolescent mental health settings. It is estimated that ADHD affects more than 5% of children. Boys are diagnosed with ADHD about twice as much as girls.

ADHD can continue into adulthood. The activity component is less apparent in adults, who tend to have problems with memory and concentration. They may have trouble staying organized and meeting commitments at work or at home. The consequence of poor functioning may be anxiety, low self-esteem, or mood problems. Some people turn to substances to manage these feelings.

Symptoms of attention-deficit hyperactivity disorder (ADHD)

The symptoms of ADHD — inattention, hyperactivity or impulsive behavior — often show up first at school. A teacher may report to parents that their child won't listen, is "hyper," or causes trouble and is disruptive. A child with ADHD often wants to be a good student, but the symptoms get in the way. Teachers, parents and friends may be unsympathetic, because they see the child's behavior as bad or odd.

A high level of activity and occasional impulsiveness or inattentiveness is often normal in a child. But the hyperactivity of ADHD is typically more haphazard, poorly organized and has no real purpose. And in children with ADHD, these behaviors are frequent enough that the child has a harder than average time learning, getting along with others or staying reasonably safe.

ADHD symptoms can vary widely. Here are common characteristics of the disorder in the two major groups (inattention and hyperactivity).



Many children with ADHD also show symptoms of other behavioral or psychiatric conditions. In fact, such problems may be different ways that the same underlying biological or environmental problems come to light. These associated conditions include learning disabilities and disorders characterized by disruptive behavior.

Diagnosing attention-deficit hyperactivity disorder (ADHD)

There is no single test to diagnose ADHD. For a child, a pediatrician may make the diagnosis, or may make a referral to a specialist. Parents and teachers may be alert to the problem and may have the child evaluated. For adults, a mental health professional generally performs the evaluation.

The clinician will ask about symptoms related to ADHD. Since, in children, many of these characteristics are seen in a school setting, the clinician will also ask about behavior in school. To help collect this information, the evaluator will often interview parents, teachers and other caregivers or ask them to fill out special behavioral checklists.

Since other conditions may cause the symptoms of ADHD, the medical history and physical examination are important. For example, the doctor may look for trouble hearing or vision, learning disabilities, speech problems, seizure disorders, anxiety, depression, or other behavior problems. In some cases, other medical or psychological testing may be useful to check for one or more of these conditions. These tests can sometimes help clinicians and teachers develop practical suggestions.

Expected duration of attention-deficit hyperactivity disorder (ADHD)

In most children with ADHD, symptoms begin before age 12 and last through adolescence. Symptoms of ADHD may continue into adulthood.

Risk factors and preventing attention-deficit hyperactivity disorder (ADHD)

The causes of ADHD are not fully understood. There are numerous factors that are associated with the development of ADHD. It may be difficult to avoid these factors, but addressing them may reduce the risk of developing the disorder.

Common risk factors

Treatment options

The following list of medications are related to or used in the treatment of this condition.

View more treatment options

Treating attention-deficit hyperactivity disorder (ADHD)

Although no treatment eliminates ADHD completely, many helpful options are available. The goal of treatment is to help children improve social relationships, do better in school, and keep their disruptive or harmful behaviors to a minimum. Medication can be very helpful, and it is often necessary.

Drug treatment by itself is rarely the answer. Medication and psychotherapy together usually have the best results. For example, a behavioral program may be put in place where structured, realistic expectations are set.

Stimulants, such as methylphenidate (Ritalin) and forms of amphetamine (Dexedrine), have been used for many decades. They are relatively safe and effective for most children to help them focus their thoughts and control their behavior. Long-acting forms of stimulants are usually preferred for children, because one dose in the morning can provide a day-long effect.

Despite their name, stimulants do not cause increased hyperactivity or impulsivity. If the disorder has been properly diagnosed, the medication should have the opposite effect. Common mild side effects are decreased appetite, weight loss, stomachaches, sleep problems, headaches and jitteriness. Adjusting the dose can often help eliminate these problems. Stimulant drugs are associated with some serious concerns and side effects.

Since such risks vary widely depending on the individual, it is important to discuss the potential benefits and risks of each treatment with your doctor.

Another potential problem, which is not strictly speaking a side effect, is that stimulants can find their way to people other than the person being treated for ADHD. Called "diversion," it is fairly common among adolescents and young adults. The drugs are most often taken to improve academic performance. Some individuals do take stimulants to get high.

Other non-stimulant medications are also available to treat ADHD. These are especially useful when there is reluctance to start a stimulant. Atomoxetine (Strattera) or viloxazine (Qelbree) can be effective for treating ADHD. They work by a different chemical mechanism than stimulants. The antidepressant, bupropion (Wellbutrin), is helpful in some cases. Two other medicines — guanfacine and clonidine — also shown some benefit for ADHD symptoms, but they have weaker effects than stimulants.

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

Because many children with ADHD also are troubled by poor grades and school behavior problems, schools may need to 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.

Additional info

American Academy of Child and Adolescent Psychiatry (AACAP)

Further information

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