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Attention-Deficit/Hyperactivity Disorder, Adult

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Attention-deficit/hyperactivity disorder is a neurobehavioral disorder characterized by a combination of inattention, hyperactivity, and impulsive behavior. Symptoms related to inattention can include difficulty sustaining focus, being forgetful in daily activities, and problems with organizing and following through. Hyperactivity symptoms may include frequent fidgeting, restlessness, impulsive behaviors, and excessively talking or interrupting others.

ADHD is considered a developmental disorder, meaning it is present from childhood onward. In recent years, however, some researchers have argued that an adult-onset form of ADHD may exist, though the debate remains ongoing and many prominent experts remain skeptical. Early in life, ADHD usually manifests as behavioral problems at school or difficulty focusing, understanding material, or completing tasks. In adulthood, it may manifest as problems achieving goals or meeting deadlines at work, social challenges caused by impulsive or reckless behavior, or frequently getting distracted during everyday activities.

According to the CDC, more than 9 percent of school-age children were diagnosed with ADHD in 2016; in adults, the prevalence is usually estimated to be between 2 and 6 percent. Boys are diagnosed more often than are girls, though heightened awareness of how ADHD typically presents in girls has decreased this disparity in recent years. Girls and women are more likely to be diagnosed with inattentive-type ADHD; however, some experts question whether this is primarily due to an actual gender difference or whether it's due, at least in part, to stereotypes that are more likely to paint young boys as “hyper.” While ADHD is often first diagnosed and treated during childhood, many individuals do not receive a diagnosis until adulthood.

Symptoms of ADHD can usually be treated effectively with medication, therapy, or a combination of the two. When left untreated, however, ADHD can have long-term adverse effects on academic performance, vocational success, relationships, and social-emotional development.


To be diagnosed with ADHD, a person must present with problems related to inattention and/or hyperactivity-impulsivity for a period of at least six months that significantly negatively impact their performance or functioning, according to the DSM-5. These behaviors must also exist in two or more contexts such as at home, at work, or in social settings. Per the DSM, these symptoms must have been present before the age of 12, even if the individual is diagnosed as an adult.

Symptoms of inattention include:

  • Making careless mistakes, overlooking details
  • Difficulty remaining focused on tasks or conversations
  • Being easily distractible
  • Difficulty following through on instructions or duties; becomes easily sidetracked
  • Difficulty organizing tasks, activities, and belongings; struggles to manage time efficiently or meet deadlines
  • Avoidance or refusal of activities that require sustained attention (reports, forms, reviewing papers)
  • Losing things frequently
  • Being forgetful of daily activities (appointments, chores)

Symptoms of hyperactivity and impulsivity include:

  • Frequent fidgeting, squirming, tapping
  • Often leaving seat when remaining seated is expected
  • Frequent pacing, running, or climbing when it is inappropriate to do so
  • Feeling overly restless
  • Experiencing discomfort when made to be still for an extended period of time
  • Difficulty engaging in leisure activities
  • Talking excessively
  • Preemptively blurting out answers to questions
  • Difficulty waiting for a turn
  • Interrupting others during conversation
  • Behaving impulsively, sometimes engaging in risky behavior while doing so

For more on symptoms and diagnosis, see our ADHD Center.

What are the different types of ADHD?

ADHD is generally categorized into 3 types. A diagnosis of combined presentation is made when a person presents with both hyperactivity-impulsivity and inattention symptoms for at least six months. A diagnosis of predominantly inattentive type is made when a person presents with criteria for inattention symptoms but not for hyperactivity-impulsivity symptoms for at least six months. A diagnosis of predominantly hyperactive-impulsive type is made when a person presents with criteria for hyperactivity-impulsivity symptoms but not for inattention symptoms for at least six months.

Is inattentive-type or hyperactive-type more prevalent in adults?

In adults with ADHD, symptoms of inattention are generally more prominent, and many adults who receive a later-in-life diagnosis are diagnosed with inattentive-type or combined-type. Such men and women with ADHD tend to struggle to focus on tasks or prioritize activities, which in turn may lead to difficulty completing work, missed deadlines, and forgotten social engagements. However, it is possible for adults to be diagnosed with predominantly hyperactive-type ADHD; these individuals may struggle most with feelings of restlessness, impulsive or even reckless behavior, and social difficulties such as frequently interrupting others.

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The causes of ADHD are still being explored, though the most substantiated causes appear to fall in the realm of neurobiology and genetics. Environmental factors may further influence the severity of the disorder. ADHD does not arise purely from poor diet, bad parenting, or screen time, contrary to popular myths.

Research on the casual elements of ADHD tends to focus on younger children. In terms of genetics, 25 percent of close relatives of a child with ADHD also have the condition—indicating that genetics play an important role in the development of ADHD. Research by the Child Psychiatry Branch of the National Institute of Mental Health found that compared to children without ADHD, children with the condition generally have a 3 to 4 percent reduction in volume in important regions of the brain including the frontal lobes, temporal gray matter, caudate nucleus, and cerebellum. These brain structures play a vital role in solving problems, planning ahead, restraining impulses, and understanding the behavior of others.

Environmental agents may also contribute to ADHD. A correlation has emerged between the use of cigarettes and alcohol during pregnancy and the risk of ADHD, for example. High levels of lead found in older buildings and exposure to lead through water sources are also implicated in the risk of developing ADHD.

Social theorists and clinicians sometimes refer to ADHD as a "disease of modernity," arguing that the fast-paced nature of modern society—and the many things that compete for our attention at all times—are responsible for the dramatic spike in ADHD seen in recent years. Some evolutionary psychologists contend that ADHD-like traits may have even been useful to our hunter-gatherer ancestors, though they’re seen as problematic today.

For more on causes and risk factors, visit our ADHD Center.

Does adult-onset ADHD exist?

Per the DSM-5 definition of ADHD, no—symptoms must be present from age 12 or earlier in order for someone to qualify for a diagnosis. In recent years, however, some longitudinal studies that followed participants from childhood to adulthood reported that some individuals appeared to meet the threshold for an ADHD diagnosis in their teen or adult years, despite not qualifying for one during childhood. The researchers concluded that ADHD may not always have a childhood onset. However, some follow-up studies argued that what was classified as “adult-onset ADHD” may have actually been something else, such as side effects from substance use or a related condition such as bipolar disorder. Other experts argue that seemingly “late-onset” ADHD symptoms may have been present all along, and were simply missed at earlier examinations. Further research is needed to definitively answer the question of adult-onset ADHD.


ADHD can be treated successfully with therapy and/or medication. Therapy can provide skills to help the person direct themselves to tasks and become more knowledgeable about their behavior to regulate it effectively. Medications can help boost focus, quell restlessness, and improve the progress made from social skills learned in therapy.

The medications most commonly prescribed to treat ADHD include a class of drugs called stimulants that have both short-acting and long-acting properties. Short-acting medications may need to be taken more often, and long-acting drugs can usually be taken once daily. Those commonly prescribed include amphetamine/dextroamphetamine (sold under the brand names Adderall and Mydayis), dexmethylphenidate (Focalin), lisdexamfetamine (Vyvanse), and methylphenidate (sold as Ritalin, Quillivant, Daytrana, QuilliChew, Concerta, and others).

Nonstimulant medications, which include atomoxetine (sold under the brand names Strattera), guanfacine (Intuniv), and clonidine (Kapvay) may be used if stimulants are ineffective or contraindicated for a particular patient. Antidepressants may also be considered for the treatment of adults with ADHD. Similar to stimulants, antidepressants target norepinephrine and dopamine neurotransmitters. Those most often used include the older class of drugs called tricyclics, but also newer antidepressants such as venlafaxine (Effexor) and bupropion (Wellbutrin). These medications can also help with nicotine cravings and smoking cessation.

Generally, hyperactivity symptoms are less prevalent in adulthood, but symptoms of inattention and impulsivity often persist. Therapy for adults with ADHD generally incorporates skills to improve everyday functions such as time management, organization, goal execution. Therapy also helps target emotion regulation, impulse control, and stress management. By improving emotional and interpersonal self-regulation, adults can more confidently navigate work as well as familial and social relationships.

Many adults with ADHD have received negative social feedback—from parents, teachers, employers, and peers—through the course of their academic or employment history that can damage their confidence, self-esteem, or beliefs about their capabilities. Cognitive behavioral therapy (CBT) can help identify negative biases in thinking that reduce motivation and perpetuate avoidance behaviors and help cultivate a range of adaptive behaviors. Mindfulness mediation training can also improve sustained attention to tasks and the ability to work through problems.

Treatment may also be targeted towards other mood and anxiety disorders that commonly co-occur in adults with ADHD.

What is the most effective treatment for ADHD in adults?

Usually, a combination of medication and therapy is thought to be the most effective way to treat ADHD in adults. Medication can help manage day-to-day symptoms of inattention or restlessness, while therapy can help strengthen practical skills, such as time management and organization, while also helping adults come to terms with their ADHD and the challenges it has caused throughout their life. Therapy can also help with the comorbid conditions many adults with ADHD struggle with, such as depression, anxiety, or insomnia. Though therapy and medication work well in concert, some adults find that just one approach in isolation is sufficient to control their symptoms. Many adults also focus on lifestyle changes, such as exercising more regularly or starting a meditation practice, that have been shown to help with the daily management of ADHD.

What is the best medication for adult ADHD?

There is no one-size-fits-all medication for ADHD, and most adults find their “best” medication through a process of trial and error. Adults who wish to try medication will generally be put on a stimulant first, unless they have a comorbid condition such as cardiovascular disease or bipolar disorder that makes such medications risky. Doctor and patient will work together to determine the dose and schedule that most effectively controls symptoms with tolerable side effects. If the first medication is found to be ineffective, another will typically be tried; if stimulants are not effective or not recommended, nonstimulants or antidepressants may be prescribed.

American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition
Barkley R.A. (2000). Taking Charge of AD/HD. New York: The Guilford Press, p. 21.
Biederman J, Faraone SV, Keenan K, Knee D, Tsuang MF. (1990) Family-genetic and psychosocial risk factors in DSM-III attention deficit disorder. Journal of the American Academy of Child and Adolescent Psychiatry, 29(4): 526-533.
Consensus Development Panel (CDP) (1982). Defined Diets and Childhood Hyperactivity. National Institutes of Health Consensus Development Conference Summary, Volume 4(3).
Faraone SV, Biederman J. (1998) Neurobiology of attention-deficit hyperactivity disorder. Biological Psychiatry, 44, 951-958.
Harvard Mental Health Letter (2002). Attention Deficit Disorder in Adults. Vol. 19:5, 3-6.
The MTA Cooperative Group. A 14-month randomized clinical trial of treatment strategies for attention-deficit hyperactivity disorder (AD/HD) (1999). Archives of General Psychiatry, 56:1073-1086.
National Institute of Mental Health (2006). Attention-Deficit/Hyperactivity Disorder. Bethesda (MD): National Institute of Mental Health, National Institutes of Health, US Department of Health and Human Services.
National Institutes of Health - National Library of Medicine - MedlinePlus, 2007. Attention deficit hyperactivity disorder (AD/HD).
US Department of Justice (USDOJ) (2006). A Guide to Disability Rights Laws. Civil Rights Division: Disability Rights Section
U.S. Department of Transportation, National Highway Traffic Safety Administration. State Legislative Fact Sheet, April 2002.
Wilens TC, Faraone, SV, Biederman J, Gunawardene S. (2003). Does stimulant therapy of attention-deficit/hyperactivity disorder beget later substance abuse? A meta-analytic review of the literature. Pediatrics, 111:1:179-185.
Wilens, TE, Biederman, J, Spencer, TJ. Attention (2002). deficit/hyperactivity disorder across the lifespan. Annual Review of Medicine, 53:113-131.
Knouse, LE, & Safren, SA (2010), Current Status of Cognitive Behavioral Therapy for Adult Attention-Deficit Hyperactivity Disorder. Psychiatric Clinics of North America, Volume 33, Issue 3, Pages 497-509
Ruff, M.E. (2005). Attention deficit disorder and stimulant use: an epidemic of modernity. Clinical Pediatrics, 44, 557-563.
Last updated: 01/06/2022