Attention Deficit Hyperactivity Disorder (ADHD): Symptoms in Adults

Discover the three types of Attention Deficit Hyperactivity Disorder (ADHD) diagnoses, how symptoms differ between kids and adults, and where to get a diagnosis.

By Ability Central

10 February, 2023

Woman of color sits at her computer, distracted

Attention Deficit Hyperactivity Disorder (ADHD) symptoms vary widely between children and adults. This difference often makes diagnosis more complicated in adults. In this article, Ability Central will answer the following questions:

  • What are the different types of ADHD?
  • What are the symptoms of ADHD in childhood?
  • What are the symptoms of ADHD in adulthood?
  • Can childhood ADHD go away before adulthood?
  • How does ADHD affect communication? 
  • What other diagnoses mimic ADHD?
  • How do I get an accurate diagnosis?
  • Where can I find more information about ADHD in adults?


What are the different types of ADHD?

There are three types of ADHD, which are defined based on how symptoms present themselves.

  1. Predominantly Inattentive Presentation is ADHD when it is hard for the individual to organize or finish a task, pay attention to details, or follow instructions or conversations. The person is easily distracted or forgets details of daily routines.
  2. Predominantly Hyperactive-Impulsive Presentation means the person fidgets and talks a lot. It takes work to sit still for a meal or do homework. The individual feels restless and has trouble with impulsivity. The person may interrupt others, grab things from people, or speak at inappropriate times. A person with impulsiveness may have more accidents and injuries than others.
  3. Combined Presentation: Symptoms of the above two types are equally present in the person.


What are the symptoms of ADHD in childhood?

People with ADHD have structurally different brains than people without it. Studies show that they have smaller volumes in five brain regions that govern things like motivation and emotion. These differences were most obvious in children, but still existed for adults.


Because of these structural differences, children with ADHD have trouble focusing and behaving. While all children struggle with behavioral challenges, children with ADHD do not just grow out of it. The symptoms continue, can be severe, and cause difficulty at school, home, or with friends. 


Symptoms may include the following:

  • Daydreaming a lot
  • Forgetting or losing things
  • Squirming or fidgeting
  • Excessive talking
  • Making careless mistakes 
  • Taking unnecessary risks
  • Struggling to take turns
  • Having difficulty getting along with others


What are the symptoms of ADHD in adulthood?

Symptoms in adults tend to be more subtle and can be misinterpreted as personality flaws or character traits. In adults, ADHD symptoms may include the following:

  • Fidgeting or tapping hands and feet
  • Restlessness
  • Inability to sit still for long periods
  • Talking too much
  • Interrupting others
  • Frequent mood swings 
  • Participating in risky behaviors 
  • Inability to pay attention to details 
  • Difficulty staying focused
  • Difficulty organizing tasks and belongings
  • Struggling with prioritization and time management
  • Forgetting day-to-day things, like paying bills, appointments, and deadlines


Can childhood ADHD go away before adulthood?

ADHD is a childhood disorder, meaning the symptoms must be present before adolescence. The symptoms may change over time, with hyperactivity and impulsivity being more pronounced in young children, while teens and young adults often display more difficulty with attention. As many as half of children diagnosed with ADHD will outgrow their symptoms before adulthood.


How does ADHD affect communication? 

The distractions, impulsiveness, and difficulty with paying attention brought about by ADHD can affect communication, resulting in interruptions, disorganized thoughts, and trouble following conversations.


These communication challenges can have a profound effect on a person's quality of life and can impact their ability to work, socialize, and maintain relationships.



What other diagnoses mimic ADHD?

The healthcare provider must rule out alternative explanations for ADHD-like behavior during the evaluation process. These may include:

  • Environmental conditions, such as changes at home or to the family unit
  • Sleep issues
  • Anxiety
  • Depression
  • Disruptive behavior disorders
  • Bipolar disorder
  • Obsessive-Compulsive Disorder (OCD)
  • Substance abuse
  • Autism


How do I get an accurate diagnosis?

You can start your diagnostic journey as an adult with a free online self-assessment. After that, an ADHD diagnostic evaluation should be conducted by a licensed mental health professional or a physician. Ask about their training and experience in working with adults with ADHD. 


Local support groups are an excellent way to find reputable resources for evaluation.


Where can I find more information about ADHD in adults?

For more information on ADHD in adults, see Ability Central’s library of resources, including:


Article Type:
Disability Type:
Attention Deficit Hyperactivity Disorder (ADHD)