Comparing Symptoms of ADHD in Children and Adults

by Eileen Bailey Health Writer

Symptoms of ADHD in children look different than in adults. Even though adults with ADHD have had it since childhood, even if they have just recently been diagnosed, there are some differences. How ADHD symptoms manifest changes as people mature into adults. The main symptoms: inattention, hyperactivity and impulsiveness remain, but how they look and how they impact an adult's life is different than how symptoms look and impact the life of a child.

The following is a comparison of how the three main symptoms may look in childhood and adulthood:


Children with hyperactivity have often been described as being in constant motion, "as if driven by a motor." In addition they may:

  • Run and climb excessively, even when inappropriate for the situation

  • Constantly fidget or squirm, needs to have something in hand to play with

  • In the classroom will get up from seat during times when the class is supposed to remain seated, will drop pencils, cause a distraction by moving around

  • Can't sit still, has a hard time playing games that require sitting for extended periods of time, doesn't like participating in quiet activities

  • Talking excessively

Adults with hyperactivity may have outgrown seeming to be "driven by a motor." Their hyperactivity may have been replaced by a general feeling of restlessness. Some other ways hyperactivity shows up in adults:

  • Needs constant motion, may tap feet, play with a pencil, doodle or fidget

  • Easily bored, moving from job to job after becoming bored once you have learned the job, leaves projects uncompleted because you became bored half-way through the project. Can complete jobs and projects if it is something you have an intense interest in.

  • Restlessness. Still have trouble sitting still for extended periods. May feel the need to get up, walk around after sitting still for a few minutes. Like activities and jobs that require movement.

  • Active, risky or fast paced activities are more apt to hold your interest


Inattention in children is frequently referred to as "easily distracted." This can be used to describe adults with ADHD as well and many of the symptoms of inattention are similar in both adults and children.

Symptoms in children:

  • Makes careless mistakes in schoolwork

  • Doesn't pay attention to details

  • Has short attention span as compared to other children of the same age, avoids activities that require sustained attention and mental effort (such as homework or schoolwork)

  • Seems to not listen when spoken to

  • Doesn't complete homework, projects or chores, becomes distracted, moves from activity to activity

  • Difficulty with organizational skills

  • Loses things

  • Forgetful

Symptoms of inattention in adults:

  • Lose and misplace items needed on an everyday basis, such as keys, phone numbers, important papers.

  • Forgetful, even in tasks that need to be done on a regular basis, such as taking out trash, picking up children

  • Leaving tasks uncompleted

  • Distracted easily, can begin one task, become distracted and start on something else, forgetting original task

  • Difficulty following conversations.

  • Problems with self-motivation

  • Loses track of time


Impulsiveness is seen in both children and adults with ADHD. Children who are impulsive are sometimes seen as rude or having behavioral problems. Impulsivity can cause problems in both making and maintaining friendships.

In children, impulsiveness might appear in the following ways:

  • Blurting out answers or comments during conversations, yelling out answers in school without raising hand

  • Having problems waiting their turn, may butt in line to get a drink or use the slide on the playground, doesn't like to wait for their turn while playing games

  • Interrupts others, will jump into conversations or games other children are playing

  • Acts without thinking about the risk, may jump from top of slide or run into the street without looking

In adults, impulsiveness can appear in the following ways:

  • May spend money impulsively, wreaking havoc on household budgets

  • Participates in risky behaviors, such as driving fast, gambling, risky sex

  • Interrupts others during conversations or answers questions before the question has been

  • Blurts out comments or thoughts without thinking even when comments are offensive or can hurt the other person's feelings

Eileen Bailey
Meet Our Writer
Eileen Bailey

Eileen Bailey is an award-winning author of six books on health and parenting topics and freelance writer specializing in health topics including ADHD, Anxiety, Sexual Health, Skin Care, Psoriasis and Skin Cancer. Her wish is to provide readers with relevant and practical information on health conditions to help them make informed decisions regarding their health care.