ADHD is one of the most common adolescent mental health disorders and interferes with the individual’s daily function at home, school, work and in social situations.

What Is ADHD?

Attention-deficit hyperactivity disorder (ADHD) is one of the most common adolescent mental health disorders, with estimates of its prevalence in children ranging from 5 to 11 percent. Though it is thought to be mainly in children, ADHD can also be diagnosed in adults. This condition affects children and adults differently. Most people, even those without ADHD, experience some degree of inattentive behavior from time to time. However, the inattention and impulsive behavior is more severe in people with ADHD. The behavior usually occurs more often and interferes with the individual’s daily function at home, school, work and in social situations.


There is a common misconception that a person can’t have ADHD if they are not hyperactive. However, someone can have ADHD or attention-deficit disorder (ADD) even if they are not loud, impulsive or extremely active.

ADD is a type of ADHD that doesn’t involve constant movement and fidgeting, but this is a blurry distinction. In the ’90s, medical practitioners generally agreed that all forms of attention-deficit disorder would be called attention-deficit hyperactivity disorder, even if the person wasn’t hyperactive.

Signs and Symptoms of ADHD

When an individual has difficulty focusing on one task, cannot sit still, always stays busy or rarely finished tasks they begin, this may be a sign that they have ADHD. There are other outside factors that could cause a lack of attention, such as drugs, or hyperactivity which can be caused by an energy drink. However, if the individual experiences symptoms that affect their daily lives, they should be tested for ADHD.

There are many symptoms of ADHD, however, the type of symptoms depends on one of the three types of ADHD and individual could have.

Types of ADHD

ADHD has three main categories which include inattention, hyperactive-impulsive and a combination of the two.


Individuals who have inattentive type ADHD have difficulty paying attention or focusing on one task. They’re easily distracted but do not have much trouble with impulsivity or hyperactivity. This is sometimes, unofficially, referred to as ADD.

Children with this type of ADHD may go undiagnosed because they may not be disruptive in class. They may seem shy and appear to be daydreaming most of the time. These individuals may not have significant behavior problems. But their problems with attention may still create many challenges.

Symptoms of inattention include:

  • Easily distracted by sights and sounds
  • Lack of attention to detail
  • Inability to follow instructions carefully
  • Making careless mistakes
  • Failing to finish tasks
  • Forgetfulness


Children are usually diagnosed with hyperactive ADHD more than adults are. Kids who have this type of ADHD have symptoms of hyperactivity and feel a need for constant movement. The patient with hyperactive ADHD may struggle with impulse control. Typically, these individuals don’t have much trouble with inattention. It’s often easier to spot signs of this type of ADHD as the child may struggle to sit still in class and manage their behavior.

Symptoms of hyperactive-impulsive behaviors include:

  • Fidgeting
  • An inability to stay seated
  • Running, jumping or climbing
  • Restlessness (common among adults)
  • Excessive talking at inappropriate times
  • Intruding in other people’s personal space

Combined ADHD

If the individual is diagnosed with combination type ADHD, it means their symptoms don’t exclusively fall in the inattention or hyperactive-impulsive behavior categories. A combination of symptoms from both categories is exhibited in these individuals. The National Institute of Mental Health states that most children are diagnosed with a combination-type ADHD even though the most common symptom in preschool-age children is hyperactivity.

Causes of ADHD

A specific ADHD cause is not known, however, there have been several factors linked to the disorder. Researchers say some of these factors may lead to it, including genetics, a chemical imbalance in the brain, poor nutrition and brain injury. Even though it is rumored to be a factor, sugar does not cause ADHD. This condition is also not linked to a poor school environment, food allergies or watching too much television.

Though ADHD cannot be prevented or cured, if it is spotted early, a good treatment and education plan may be put into place for the patient to better manage their symptoms.

Diagnosing ADHD

People who have ADHD show a persistent pattern of inattention and hyperactivity-impulsivity that interferes with functioning or development. The individual’s physician will complete physical ADHD tests to rule out any other physical possibilities before referring the patient to a mental health professional.

The Diagnostic Statistical Manual states that there are different requirements for diagnosing each type of ADHD. The individual must contain six or more symptoms that are related to that specific type. This is a huge factor in the reason combination type ADHD is the most widely diagnosed.

ADHD in Children

Because children are not finished growing mentally and do not have the coping mechanisms of an adult, they are affected differently by mental illnesses.

Children with ADHD often find it difficult to concentrate on schoolwork or other tasks and may frequently daydream while they are supposed to be doing other activities. Some children with ADHD become disruptive, defiant and have trouble getting along with others. Children who struggle with hyperactivity and impulsivity have more behavioral challenges than adults.

Overall, 5 to 11 percent of children and adolescents are diagnosed with ADHD every year. Children and teens with ADHD may benefit from accommodations at school to help adapt classroom environments and testing procedures to the students’ learning styles.

ADHD in Adults

Many adults who live with ADHD do not realize they have the disorder. To diagnose this disorder, it is important for medical professionals to conduct a comprehensive evaluation, including a review of past and current symptoms and a medical exam. ADHD adults are usually treated with medication, psychotherapy or a combination of the two. Behavior management strategies and involving immediate family members can also be helpful.

When a child has ADHD, the disorder often lasts into adulthood. Symptoms might look different at older ages. For example, in adults, hyperactivity may appear as extreme restlessness, always staying busy or wearing other people out with their activity.

ADHD Statistics

According to the American Psychological Association, approximately 5 percent of American adults have ADHD. That represents more than 11,000,000 people. This mental illness occurs in both men and women, but males are almost three times more likely to be diagnosed with ADHD than females. During their lifetimes, 12.9 percent of men will be diagnosed with an attention disorder while only 4.9 percent of women will be diagnosed.

Until recently, ADHD was considered a childhood disorder that individuals eventually grew out of. While evidence still suggests that up to 50 percent of children with ADHD do appear to see a decrease in symptoms as they age, many others do not. The average age of an ADHD diagnosis is seven years old with symptoms first appearing between the ages of three and six.

ADHD and Substance Abuse

Young adults with ADHD are more likely to use alcohol excessively. Researchers have also found links between ADHD and the use of marijuana and other recreational drugs, particularly in individuals who also have co-existing psychological disorders like anxiety or depression. People who struggle with ADHD typically start having problems with drugs and alcohol at an earlier age than people without the condition.

Individuals with ADHD tend to display impulsive behavior, which may contribute to drug and alcohol abuse. Both ADHD and alcoholism tend to be genetic. Research suggests that when a child who has ADHD also has an alcoholic parent, the child is more likely to also develop an alcohol abuse problem later in their life.

If you or a loved one needs treatment for substance abuse and a co-occurring disorder like ADHD, The Recovery Village can help. Individuals who struggle with drug or alcohol abuse and co-occurring ADHD symptoms can receive compassionate treatment from one of the facilities located across the country. To learn more, call The Recovery Village today to speak with a representative.

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Editor – Camille Renzoni
Cami Renzoni is a creative writer and editor for The Recovery Village. As an advocate for behavioral health, Cami is certified in mental health first aid and encourages people who face substance use disorders to ask for the help they deserve. Read more
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Medically Reviewed By – Krisi Herron, LCDC
Krisi Herron is an Adjunct Psychology Professor, a Licensed Chemical Dependency Counselor and a freelance writer who contributes to several mental health blogs. Read more


Can ADHD Cause Hypersomnia?

While attention-deficit hyperactivity disorder (ADHD) can co-occur with hypersomnia and other sleep disorders, it is unknown whether ADHD actually causes hypersomnia. One study conducted in 2006 discovered that children with ADHD were more likely than other children to have daytime sleepiness, which is the main symptom of hypersomnia. Another study in 2004 found that half of children with ADHD had sleep-disordered breathing.

Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.