Signs and Symptoms of ADHD

young boy with adhd showing signs of hyperactivity and jumping on the couch

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  • ADHD is a disorder that can affect your thinking, behavior, and ability to function.
  • There are three primary symptoms of ADHD: inattention (being distracted), hyperactivity (feeling restless), and impulsivity (making hasty decisions).
  • Symptoms commonly appear during childhood, but can also linger into adulthood.

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder—or, a condition that affects proper brain growth and development. Generally, ADHD symptoms show up during childhood and can last into adulthood. But, these symptoms may change as a child gets older.

Symptoms of ADHD fit into three major categories: inattention, hyperactivity, and impulsivity. Children with ADHD may experience symptoms in only one category. However, some people have symptoms in more than one category. ADHD symptom categories help lay the foundation for the three main types of ADHD. The type of ADHD you or your child has depends on their most dominant (strongest) symptom. These types include:

  • Predominantly inattentive ADHD
  • Predominantly hyperactive-impulsive ADHD
  • Combined ADHD

ADHD symptoms affect how a person thinks, behaves, and expresses their emotions. Because of this, ADHD can affect many areas of a person’s life, such as their performance in school or at work, how they navigate relationships, and their ability to carry out daily tasks.

It’s normal for people to have moments of inattention, hyperactivity, and impulsivity from time to time. But in the case of ADHD, these symptoms last for more than six months. If you are concerned that you or your child might be displaying signs of ADHD, knowing the hallmark symptoms of the condition can encourage you to speak to a healthcare provider for testing and further support.

Common Symptoms

While there are three primary types of ADHD, all three types share some common symptoms. Generally, young children may show one or more of the following signs:

  • Trouble listening to or following instructions 
  • Restlessness or fidgeting with their hands and feet
  • Talking too much
  • Difficulty paying attention to details
  • Not being able to finish projects, chores, or homework

Symptoms of Predominantly Inattentive ADHD

People with predominantly inattentive ADHD may often find it difficult to stay focused, have trouble following directions, and may appear to be daydreaming or off-task. It’s important to note that your or your child’s inattention is not an act of disobedience or a lack of understanding. Rather, the condition itself causes these symptoms to occur.

In order to receive a diagnosis for inattentive-type ADHD, symptoms must last for at least six months. Common signs and symptoms of this type of ADHD include, but are not limited to:

  • Forgetfulness
  • Disorganization
  • Being easily distracted
  • Losing or misplacing things
  • Poor concentration or attention to detail
  • Not be able to complete assignments and tasks

Symptoms of inattention typically appear around the age of eight or nine years old. Children may have these symptoms at a younger age while at home. However, inattention may become more obvious while the child is at school given the environment—such as needing to pay attention in class and completing homework assignments. Many people with this type of ADHD usually experience these symptoms through their teenage years and early adulthood.

Symptoms of Predominantly Hyperactive-Impulsive ADHD

In younger children, hyperactive and impulsive behaviors almost always occur together. Predominantly hyperactive-impulsive ADHD is characterized by having trouble sitting still, making hasty decisions, or performing behaviors without understanding the consequences of their actions.   

With hyperactive-impulsive type ADHD, you may also notice that you or your child are displaying one or more of the following symptoms:

  • Excessive fidgeting while sitting down
  • Difficulty taking turns with others 
  • Blurting things out in class  
  • Intruding or interrupting conversations or activities
  • Answering questions before they are fully asked
  • Frequent restlessness 
  • Having a lot of energy 

Similarly to inattentive-type ADHD, symptoms must be present for at least six months before a healthcare provider can provide an accurate diagnosis. 

Hyperactivity and impulsivity typically appear around the age of four years old. Although impulsivity peaks around seven or eight years old, these symptoms may last throughout a person’s life. However, hyperactivity symptoms start to become less noticeable in adolescents.

Symptoms of Combined ADHD

People who receive a diagnosis for combined ADHD present symptoms of both inattentive ADHD and hyperactivity-impulsivity ADHD. Usually, people living with combined ADHD have an equal amount of symptoms from both types. 

Along with symptoms specific to both types of ADHD, people with combined ADHD may have trouble reaching their full potential at school or work and find difficulty in making friends or maintaining meaningful relationships. 

To receive an accurate diagnosis for combined ADHD, symptoms from both types of ADHD must be present for at least six months.

Symptoms in Adults

Although symptoms first appear during childhood and adolescence, adults can also have ADHD as they transition from their teenage years into early and middle adulthood. Some studies also show that people can develop ADHD symptoms during adulthood, but more research is needed to understand why this happens.

Adults experience the same three types of ADHD as children, but symptoms of each type can sometimes look different as you age. For example, adults with undiagnosed ADHD might have difficulty keeping a stable job because it’s hard for them to get up in the morning or go to work on time. People with hyperactivity symptoms may also try to complete several tasks at the same time, which can often end in unsuccessful results. Those with inattentive ADHD may forget to pay bills or lose important documents and objects.

Similar to children and teenagers, ADHD symptoms can often interfere with relationships, work life, and personal well-being. These symptoms can also become more severe as you get older, which can happen because daily tasks and life’s demands in adulthood increase. 

Symptom Differences in Men and Women

ADHD is more commonly diagnosed in boys compared to girls. This occurs because research on ADHD has historically been studied on boys. Young boys tend to have symptoms of hyperactivity, while young girls display signs of inactivity.

Currently, boys receive an ADHD diagnosis far more often than girls. Keep in mind: this does not mean that boys are more likely to have ADHD. Instead, more research is needed to understand how ADHD symptoms can present themselves differently in young girls and women.

When to See a Healthcare Provider

It’s normal to experience inattention, impulsivity, or hyperactivity from time to time. In the case of ADHD, these behaviors are often more severe, occur more frequently, and can have a negative effect on everyday tasks and yours or your child’s quality of life.

ADHD is considered a chronic disorder. As with any other chronic condition, early diagnosis and treatment can help manage ADHD symptoms. If you’ve noticed that you or your child may be displaying symptoms of ADHD, it’s a good idea to make a visit to your primary healthcare provider or your child’s pediatrician. They can refer you to a psychologist or psychiatrist and help you figure out next steps for diagnosis and treatment.

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  9. National Institute of Mental Health. Attention-deficit/hyperactivity disorder.

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