Symptoms of Adult ADHD

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Attention deficit hyperactivity disorder (ADHD) is a medical condition that affects the brain’s development. As a result, a person with ADHD may have difficulty paying attention, sitting still, or controlling impulsive behaviors.

ADHD is a developmental disorder that is typically diagnosed in childhood; however, it can persist into adulthood as well. Approximately 2.5% of adults have ADHD.

The symptoms of ADHD are broadly classified into two categories: 

  • Symptoms of inattention
  • Symptoms of hyperactivity and impulsivity

This article explores the symptoms of adult ADHD, as well as the diagnostic criteria for this condition.

Symptoms of Inattention

These are some of the symptoms of inattention that people with ADHD may display:

  • Difficulty concentrating on tasks such as work assignments or chores
  • Strong dislike or avoidance of tasks that require applying mental effort for a long period of time, such as creating reports, filling out forms, or reviewing paperwork
  • Forgetfulness, which can result in unpaid bills, missed appointments, and unreturned calls
  • Tendency to lose or misplace things, such as wallet, keys, or phone
  • Lack of attention to detail, resulting in careless mistakes
  • Tendency to get distracted easily by unrelated factors
  • Failure to complete tasks before starting new ones
  • Poor organization and time management skills
  • Difficulty listening to others and following through on instructions

Symptoms of Hyperactivity and Impulsivity

These are some of the symptoms of hyperactivity and impulsivity that people with ADHD may display:

  • Fidgeting or tapping their hands and feet
  • Pacing or moving around, rather than remaining seated
  • Feeling restless and unable to sit still
  • Seeming like they’re always on the go or wearing others out with their activity
  • Having difficulty sitting through work and other activities
  • Talking excessively
  • Speaking out of turn
  • Blurting out responses before a question has been completed
  • Intruding in others’ conversations

Diagnostic Criteria for Adult ADHD

ADHD can be diagnosed by a qualified healthcare provider such as a primary care physician, a therapist, or a psychiatrist. In some cases, the primary care physician may refer a patient to a mental healthcare provider, if they suspect the person has ADHD.

The healthcare provider will assess the person and determine whether they meet the diagnostic criteria for ADHD listed in the Diagnostic and Statistical Manual. The manual, published by the American Psychiatric Association, helps healthcare providers diagnose and treat mental health conditions such as ADHD.

These are the diagnostic criteria for ADHD listed in the DSM-5, for people over the age of 17:

  • Having at least five symptoms of inattention for over six months
  • Having at least five symptoms of hyperactivity and impulsivity for over six months
  • Experiencing several of these symptoms since before the age of 12
  • Exhibiting symptoms in two or more different settings, such as at home, at work or school, with friends or family members, or during other activities
  • Facing disruptions to their daily life or reduced ability to function at work or in social settings due to their symptoms
  • Behaving in ways that are inappropriate for their age and developmental level
  • Not having any other health condition that would account for the presence of these symptoms

Types of ADHD

Based on the person’s symptoms, they may be diagnosed with one of three types of ADHD:

  1. Combined type ADHD: The person has had symptoms of inattention as well as hyperactivity and impulsivity for over six months.
  2. Predominantly inattentive ADHD: The person has had considerable symptoms of inattention, but not too many symptoms of hyperactivity-impulsivity over the last six months.
  3. Predominantly hyperactive-impulsive ADHD: The person has had considerable symptoms of hyperactivity-impulsivity, but not too many symptoms of inattention over the last six months.

Childhood vs. Adult ADHD

Many adults with ADHD don’t realize they have the condition. ADHD in adults hasn’t been studied as extensively as ADHD in children and is harder to define. Adult ADHD symptoms may be more subtle, or look different than they do in childhood.

The diagnostic criteria are also slightly different for adults than for children. For instance, the diagnostic criteria for children states that the person needs to have at least six of the symptoms of inattention and six of the symptoms of hyperactivity and impulsivity. In people above the age of 17, the diagnostic criteria requires the person to have five symptoms of each type.

ADHD is not acquired in adulthood; it is a developmental disorder that begins in childhood. However, the symptoms may persist into adulthood. Therefore, the diagnostic criteria state that the person should have experienced the majority of the symptoms since before the age of 12. Adults with ADHD often have a pattern of history at school, college, and work.

An adult may not have been diagnosed with ADHD as a child if:

  • Their family members and teachers did not recognize the condition when they were young
  • They had a mild form of ADHD
  • They were able to cope with the condition when they were younger, but started experiencing challenges when faced with the more rigorous demands of college or work

Complications With ADHD

In addition to ADHD, people may also have other mental health conditions such as:

  • Depression
  • Anxiety disorders
  • Sleep disorders
  • Bipolar disorder
  • Personality disorders
  • Obsessive compulsive disorder (OCD)
  • Autism spectrum disorder (ASD)
  • Epilepsy
  • Tourette's syndrome
  • Learning difficulties, such as dyslexia

A Word From Verywell

Adult ADHD can make it difficult for a person to function at work and in social settings. A person with ADHD may have difficulty with daily tasks such as getting ready, reaching work on time, focusing on work, holding down a job, or maintaining relationships. They may often feel restless and try to do multiple things at once, often without much success.

Identifying the symptoms of ADHD and seeking treatment can help improve quality of life. Adult ADHD treatment can include medication and therapy, or a combination of both. While people tend to associate ADHD with children, there is growing awareness that it can affect adults as well. It's important to remember that it’s never too late to get help for this condition.

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10 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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