ADHD Signs, Symptoms & Effects

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common mental health disorders in childhood, and if effective treatment is not received, the individual may continue to experience symptoms through adolescence and into adulthood.

Understanding ADHD

Learn about ADHD

As the name of the disorder implies, symptoms of ADHD typically involve struggles related to attention, focus, and behavior control.

Depending on the nature and severity of these symptoms, a person who has ADHD may have an extremely difficult time performing to expectation in school, experiencing success in the workplace, forming and maintaining positive interpersonal relationships, and otherwise participating in a healthy and satisfying lifestyle.

Treatment for ADHD may involve medication, therapy, or a combination of the two. When an adolescent or adult receives effective treatment at a residential center, outpatient clinic, or other means, he or she may experience an easing of certain symptoms and learn to manage other symptoms in order to achieve improved quality of life.


ADHD statistics

According to the U.S. Centers for Disease Control and Prevention (CDC), about 6.4 million children and adolescents in the United States, or about 11% of individuals ages 4 to 17, meet the criteria for a diagnosis of attention-deficit/hyperactivity disorder. The National Institute of Mental Health (NIMH) reports that the 12-month prevalence of ADHD among adults in the United States is 4.1%, with about 41% of these cases being classified as “severe.”

Causes and Risk Factors

Causes and risk factors for ADHD

Considerable research suggests that a person’s risk of developing attention-deficit/hyperactivity disorder may be influenced by several genetic and environmental factors, including but not limited to the following:

Genetic: Attention-deficit/hyperactivity disorder appears to have a strong genetic component. Individuals who have a first-degree relative, such as a parent or sibling, who has ADHD are at a far higher risk of developing the disorder than are individuals who do not have a family history of the disorder. Researchers have identified specific genes that appear to be associated with an increased or decreased likelihood of developing ADHD, but they have not yet established a cause/effect relationship between these genes and the development of the disorder.

Environmental: Individuals whose mothers abused alcohol and/or tobacco during pregnancy appear to be at increased risk for developing ADHD, as are those who were abused or neglected, who were placed in multiple foster homes, or who otherwise experienced childhood adversity. Exposure to lead and other neurotoxins during childhood can also increase an individual’s risk of developing ADHD.

Risk factors:

  • Gender (ADHD is more common among boys and men than among girls and women)
  • Low birth weight
  • Maternal use of alcohol and/or tobacco during pregnancy
  • Family history of ADHD
  • History of abuse and/or neglect during childhood
  • Certain minor physical abnormalities and subtle motor delays
  • Exposure to certain environmental toxins, such as lead

Signs and Symptoms

Signs and symptoms of ADHD

The symptoms of ADHD may vary considerably depending upon several factors including the type of symptoms and the age of the individual. In general, symptoms of ADHD can be divided into two categories, inattentive and hyperactive-impulsive. The following are among the more common examples of symptoms from each category:


  • Poor organization skills
  • Tendency to procrastinate
  • Trouble starting and finishing projects
  • Trouble concentrating
  • Easily distracted
  • Makes careless mistakes
  • Frequently forgets appointments, commitments, and deadlines
  • Has a difficult time following directions


  • Fidgets and squirms while trying to sit still
  • Has difficulty staying quiet when required to do so
  • Acts without thinking through the consequences
  • Gets bored easily
  • Quick temper with short fuse
  • Racing thoughts
  • Craves excitement
  • Excessive talking, including tendency to interrupt others or talk over them
  • Has trouble waiting for his or her turn in conversations or other settings
  • Prone to temper tantrums or angry outbursts


Effects of ADHD

Without proper care at a comprehensive treatment center, outpatient clinic, or other program, the effects of ADHD can cause serious disruptions in all areas of an individual’s life. The following are among the potential long-term effects of untreated attention-deficit/hyperactivity disorder:

  • Substandard performance at work or in school
  • Job loss and unemployment
  • Inability to form and maintain healthy interpersonal relationships
  • Family discord
  • Increased risk of motor vehicle accidents
  • Physical injury due to hyperactivity and/or impulsivity
  • Diminished self-esteem
  • Pervasive sense of hopelessness
  • Substance abuse and addiction
  • Peer rejection and social isolation

Co-Occurring Disorders

ADHD and co-occurring disorders

Individuals who struggle with attention-deficit/hyperactivity disorder may also be at increased risk for experiencing the following co-occurring disorders:

  • Anxiety disorders
  • Conduct disorder
  • Major depressive disorder
  • Obsessive-compulsive disorder (OCD)
  • Oppositional defiant disorder (ODD)
  • Conduct disorder
  • Disruptive mood dysregulation disorder
  • Intermittent explosive disorder (IED)
  • Autism spectrum disorder

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– Anonymous Patient
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