Attention-deficit/hyperactivity disorder (ADHD) is a chronic condition that affects millions of children and often continues into adulthood. ADHD includes a combination of persistent problems, such as difficulty sustaining attention, hyperactivity and impulsive behavior.

Children with ADHD may also struggle with low self-esteem, troubled relationships and poor performance in school. Symptoms sometimes lessen with age. However, some people never completely outgrow their ADHD symptoms. But they can learn strategies to be successful.

While treatment won’t cure ADHD, it can help a great deal with symptoms. Treatment typically involves medications and behavioral interventions. Early diagnosis and treatment can make a big difference in outcome.

An estimated 8.4% of children and 2.5% of adults have ADHD.1, 2 ADHD is often first identified in school-aged children when it leads to disruption in the classroom or problems with schoolwork. It is more common among boys than girls.


The primary features of ADHD include inattention and hyperactiveimpulsive behavior. ADHD symptoms start before age 12, and in some children, they’re noticeable as early as 3 years of age. ADHD symptoms can be mild, moderate or severe, and they may continue into adulthood.

ADHD occurs more often in males than in females, and behaviors can be different in boys and girls. For example, boys may be more hyperactive and girls may tend to be quietly inattentive.

There are three subtypes of ADHD:

  • Predominantly inattentive. The majority of symptoms fall under inattention.
  • Predominantly hyperactive/impulsive. The majority of symptoms are hyperactive and impulsive.
  • Combined. This is a mix of inattentive symptoms and hyperactive/impulsive symptoms.

A child who shows a pattern of inattention may often:

  • Fail to pay close attention to details or make careless mistakes in schoolwork
  • Have trouble staying focused in tasks or play
  •  Appear not to listen, even when spoken to directly
  •  Have difficulty following through on instructions and fail to finish schoolwork or chores
  •  Have trouble organizing tasks and activities
  •  Avoid or dislike tasks that require focused mental effort, such as homework
  •  Lose items needed for tasks or activities, for example, toys, school assignments, pencils
  •  Be easily distracted
  •  Forget to do some daily activities, such as forgetting to do chores

Hyperactivity and impulsivity
A child who shows a pattern of hyperactive and impulsive symptoms may often:

  • Fidget with or tap his or her hands or feet, or squirm in the seat
  • Have difficulty staying seated in the classroom or in other situations
  • Be on the go, in constant motion
  • Run around or climb in situations when it’s not appropriate
  • Have trouble playing or doing an activity quietly
  • Talk too much
  • Blurt out answers, interrupting the questioner
  • Have difficulty waiting for his or her turn
  • Interrupt or intrude on others’ conversations, games or activities


There is no lab test to diagnose ADHD. Diagnosis involves gathering information from parents, teachers and others, filling out checklists and having a medical evaluation (including vision and hearing screening) to rule out other medical problems. The symptoms are not the result of person being defiant or hostile or unable to understand a task or instructions.

In general, a child shouldn’t receive an ADHD diagnosis unless the core symptoms of ADHD start early in life — before age 12 — and create significant problems at home and at school on an ongoing basis.

Although there are different ways to assess ADHD, the method supported by the most evidence-based practice is the Cognitive Assessment known as the Wechsler Intelligence Scale for Children | Fifth Edition (WISC-V) and Wechsler Adult Intelligence Scale | Fourth Edition WAIS–IV.

Other methods used with the Cognitive Assessment to diagnose ADHD, may include:

  • Medical exam, to help rule out other possible causes of symptoms
  • Information gathering, such as any current medical issues, personal and family medical history, and school records
  • Interviews or questionnaires for family members, your child’s teachers or other people who know your child well, such as caregivers, babysitters and coaches
  • ADHD criteria from the Diagnostic and Statistical Manual of Mental Disorders DSM-5, published by the American Psychiatric Association
  • ADHD rating scales to help collect and evaluate information about your child

Diagnosing ADHD in young children

Although signs of ADHD can sometimes appear in preschoolers or even younger children, diagnosing the disorder in very young children is difficult. That’s because developmental problems such as language delays can be mistaken for ADHD.

So, children preschool age or younger suspected of having ADHD are more likely to need evaluation by an ADHD specialist, such as a psychologist or psychiatrist, speech pathologist, or developmental paediatrician.


Though it’s called adult ADHD, symptoms start in early childhood and continue into adulthood. In some cases, ADHD is not recognized or diagnosed until the person is an adult. Adult ADHD symptoms may not be as clear as ADHD symptoms in children. In adults, hyperactivity may decrease, but struggles with impulsiveness, restlessness and difficulty paying attention may continue.

Treatment for adult ADHD is similar to treatment for childhood ADHD. Adult ADHD treatment includes medications, psychological counselling (psychotherapy) and treatment for any mental health conditions that occur along with ADHD.

Some people with ADHD have fewer symptoms as they age, but some adults continue to have major symptoms that interfere with daily functioning. In adults, the main features of ADHD may include difficulty paying attention, impulsiveness and restlessness. Symptoms can range from mild to severe.

Many adults with ADHD aren’t aware they have it — they just know that everyday tasks can be a challenge. Adults with ADHD may find it difficult to focus and prioritize, leading to missed deadlines and forgotten meetings or social plans. The inability to control impulses can range from impatience waiting in line or driving in traffic to mood swings and outbursts of anger.

Adult ADHD symptoms may include:

  • Impulsiveness
  • Disorganization and problems prioritizing
  • Poor time management skills
  • Problems focusing on a task
  • Trouble multitasking
  • Excessive activity or restlessness
  • Poor planning
  • Low frustration tolerance
  • Frequent mood swings
  • Problems following through and completing tasks
  • Hot temper
  • Trouble coping with stress


Brain scientists have found that deficiencies in specific neurotransmitters underlie many common disorders, including anxiety, mood disorders, anger-control problems, and obsessive-compulsive disorder.

ADHD was the first disorder found to be the result of a deficiency of a specific neurotransmitter — in this case, norepinephrine, which is linked arm-in-arm with dopamine. Dopamine is the thing that helps control the brain’s reward and pleasure centre.

There are several differences between the brains of people with ADHD and people without the condition. ADHD causes differences in both:

  • Brain function
  • Brain structure

Brain function

ADHD affects brain functioning in several ways. The condition has links to abnormal cognitive, behavioral, and motivational functioning. ADHD can affect the regulation of moods, emotions, and brain cell connections. It can also affect communication between different areas of the brain. Brain networks are groups of nerve cells, called neurons, which send information throughout the brain. The brain networks of people with ADHD may take more time to develop and be less effective at relaying certain messages, behaviors, or information. These brain networks may function
differently in areas such as focus, movement, and reward.

Imaging tools such as those based on MRIs and X-rays can measure subtle abnormalities in the structure and the function of the brains of people with neurodevelopmental disorders, including ADHD. In imaging studies of people with ADHD, there is an imbalance in the way that some brain networks are structured, which is called structural connectivity. There is also an imbalance in the way that some brain network’s function, which is called functional connectivity.

In studies designed to induce a specific brain function, such as a challenging thought-related task, or an emotion-inducing situation, researchers and scientists can look at the pattern of activity across different brain regions in people with ADHD and compare them with neurotypical individuals in order to find out how their brains differ.

Research shows that in people with ADHD, some brain regions become “hyperactive,” whereas other brain regions are “hypoactive.” This suggests that there may be a problem with the brain’s computing capacity to appropriately meet the cognitive demand of the task.

For example, a person with ADHD may be unable to suppress brain activity in the default attention network, especially as a task becomes more difficult. This may link to more distractibility.

A 2019 study Trusted Source used resting-state functional MRIs to observe the brain circuity in adults with ADHD. Researchers linked increases in functional connectivity in certain brain regions to clinical symptoms of hyperactivity and restlessness, suggesting that inefficiencies in brain network processing could explain some symptoms of ADHD.

Brain structure

There are several differences between the brain structures of people with and without ADHD. These differences affect several areas of the brain that relate to common ADHD symptoms.

A 2017 study suggests that compared with children without ADHD, children with ADHD often have slightly smaller brains, and their brains may take more time to mature. Volume differences often exist in various brain regions, including the amygdala and hippocampus, which relate to motivation, memory, and emotion regulation. It’s important to note that brain size does not affect intelligence.

According to a 2007 publication from the National Institutes of Health Trusted Source, children with ADHD have delayed brain maturation in certain areas. The most prominent delays were at the front of the cortex, which relates to cognitive, attention, and planning control. The motor cortex was the only brain region that matured quicker than usual in children with ADHD, which may relate to symptoms such as restlessness and fidgeting.

The frontal lobe controls cognitive functioning such as attention, impulse control, and social behavior. Certain areas of the frontal lobe may mature more slowly in people with ADHD. This delay may cause dysfunction related to these cognitive skills.

The premotor cortex and prefrontal cortex are parts of the frontal lobe involved in motor activity and attentional capacity. These areas of the brain may have less activity in people with ADHD


Treatment for ADHD usually includes:

  • Medicine. This activates the brain’s ability to pay attention, slow down, and use more self-control.
  • Behavior therapy. Therapists can help children develop the social, emotional, and planning skills that are lagging with ADHD.
  • Parent coaching. Through coaching, parents learn the best ways to respond to behavior problems that are part of ADHD.
  • School support. Teachers can help children with ADHD do well and enjoy school more.

The right treatment helps ADHD improve. Parents and teachers can teach younger children to get better at managing their attention, behavior, and emotions. As they grow older, children should learn to improve their own attention and self-control.
When ADHD is not treated, it can be hard for children to succeed. This may lead to low self-esteem, depression, oppositional behavior, school failure, risk-taking behavior, or family conflict.

How Can Parents Help?

If your child is diagnosed with ADHD:

  • Be involved. Learn all you can about ADHD. Follow the treatment your child’s health care provider recommends. Go to all recommended therapy visits.
  • Give medicines safely. If your child is taking ADHD medicine, always give it at the recommended time and dose. Keep medicines in a safe place.
  • Work with your child’s school. Meet often with teachers to find out how your child is doing. Work together to help your child do well
  • Parent with purpose and warmth. Learn what parenting approaches are best for a child with ADHD — and which can make ADHD worse.
    Talk openly and supportively about ADHD with your child. Focus on your child’s strengths and positive qualities.
  • Connect with others for support and awareness. Join a support group for ADHD to get updates on treatment and other information.
    ADHD can improve when kids get treatment, eat healthy food, get enough sleep and exercise, and have supportive parents who know how to respond to ADHD.


What Is a Comorbid Condition?

Comorbid conditions are distinct diagnoses that exist simultaneously with ADHD or ADD. They do not go away once the primary condition – in this case, ADHD – is treated. Comorbid conditions exist in parallel with ADHD and require their own specific treatment plan.

Doctors once considered ADHD a standalone disorder. They were wrong. We now know that 50 percent of people with ADHD also suffer from one or more additional condition, referred to as a comorbidity. Most commonly, ADHD comorbidities include:

  • Depression
  • Anxiety
  • Obsessive-compulsive disorder (OCD)
  • Oppositional defiant disorder (ODD)
  • Learning disabilities
  • Language disabilities
  • Fine and gross motor difficulties
  • Executive function difficulties
  • Tic disorders
  • Or another psychological or neurological problem

In some cases, these problems are “secondary” to ADHD — that is, they are triggered by the frustration of coping with symptoms of ADHD.
For example, a boy’s chronic lack of focus may trigger anxiety in school.

Years of disapproval and negative feedback from family members may likewise cause a woman with undiagnosed ADHD to become depressed. Most of the time, secondary problems fade once the ADHD symptoms are brought under control.

When secondary problems don’t resolve with effective ADHD treatment, they are likely symptoms of a “comorbid” condition.

Three Common ADHD Comorbidity Categories

The three categories of comorbid conditions most commonly diagnosed with ADHD all occur along a spectrum of severity — from mild to serious. Their symptoms are as varied as their causes, which range from genes to exposure to environmental toxins to prenatal trauma, and beyond.

ADHD Comorbidity #1: Cortical wiring problems Cortical writing problems are caused by structural abnormalities in the cerebral cortex, the brain region responsible for high-level brain functions.

Cortical wiring problems include:

  • Learning disabilities
  • Language disabilities
  • Fine and gross motor difficulties
  • Executive function difficulties

Cortical wiring problems are treated with academic accommodations and lifestyle changes. They do not respond to medication.

ADHD Comorbidity #2: Problems regulating emotions

Problems regulating emotions often include:

  • Depression
  • Anxiety disorders (including panic attacks)
  • Anger-control problems (intermittent explosive disorder or oppositional defiant disorder)
  • Obsessive-compulsive disorder (OCD)
  • Bipolar disorder

Note that depression can cause a range of symptoms beyond sadness and thoughts of suicide; these include irritability, reduced interest in activities that used to be pleasurable, sleep disturbances, decreased ability to concentrate, indecisiveness, agitation or slowness of thinking, fatigue or loss of energy, and feelings of worthlessness or inappropriate anger.

Regulatory problems often respond to a group of medications known as selective serotonin reuptake inhibitors, or SSRIs, which generally can be used in conjunction with ADHD medications.

Bipolar disorder is an exceedingly complex condition with many possible treatments. With this disorder especially, it’s important to work with a psychiatrist who understands how to administer medications alongside treatment for ADHD.

ADHD Comorbidity #3: Tic disorders

Tic disorders refer to sudden twitches of whole muscle groups. They vary in severity and typically include:

  • Motor tics (ranging from involuntary eye blinking to head jerking to repeated gestures)
  • Oral tics (ranging from grunting to random blurting to, in very rare cases, obscene words or phrases)
  • Tourette’s syndrome (multiple motor and vocal tics that have been present for more than a year)

How to Differentiate Symptoms of an ADHD Comorbidity from ADHD

If you or your child continue to struggle after you’ve begun treatment for ADHD, your next step is to determine whether the symptoms are secondary to ADHD (and likely to dissipate if you fine-tune your treatment plan), or evidence of a fully-fledged comorbid disorder that requires additional treatment. signs of a fully-fledged comorbid condition. There is no litmus test that can determine this. The best differential diagnosis begins with careful observation of where and when symptoms arise.

1. Secondary problems typically start at a certain time or occur only under certain circumstances. Did your daughter start experience anxiety only in the third grade? Is she anxious only in school or at home when doing homework? If so, her anxiety is likely secondary to ADHD and not a true comorbid disorder. Ditto if your son became aggressive only upon starting middle school.

2. In contrast, comorbid disorders are both chronic and pervasive. They are generally apparent from early childhood and occur in every life situation. Rather than occurring just during the school day, for instance, they persist over weekends, holidays, and summer vacation; they are evident in school, at home, at work, and in social situations. For example, ADHD-related mood shifts are usually triggered by life events. Bipolar mood shifts, on the other hand, may appear to come and go without any connection to the outside world, and may be sustained over longer periods of time. As with ADHD, they are often hereditary.

Consult a child and adolescent psychiatrist or Clinical psychologist.

If you suspect that your child has more than just ADHD, it’s time to request an assessment designed to identify learning, language, motor, or organization/executive function problems. You may also need to pursue a clinical evaluation to determine if your child is living with anxiety, depression, anger control, OCD, or a tic disorder.


While the exact cause of ADHD is not clear, research efforts continue.

Factors that may be involved in the development of ADHD include:

  • Genetics. ADHD can run in families, and studies indicate that genes may play a role. There is evidence that genetics contribute to ADHD. For example, three out of four children with ADHD have a relative with the disorder.
  • Environment. Certain environmental factors also may increase risk, such as lead exposure as a child.
  • Problems during pregnancy and development. Problems with the central nervous system at key moments in development may play a role. Other factors that may contribute to the development of ADHD include being born prematurely, brain injury and the mother smoking, using alcohol or having extreme stress during pregnancy.