Attention deficit hyperactivity disorder (ADHD) is a chronic condition characterized by impulsive behavior, inattention, and hyperactivity.
It's usually diagnosed in childhood, but the symptoms of ADHD can continue unrecognized through adolescence and adulthood, so it may not be diagnosed for the first time until someone is an adult. With proper treatment, children and adults with ADHD can live successful, productive lives.
Signs and Symptoms of ADHD
Attention deficit disorder (ADD) is an older term for what's now known as ADHD. While some people still use the terms ADD and ADHD interchangeably, and may call the condition ADD if a child only has trouble focusing and isn't hyperactive, ADHD is officially recognized as the correct term for this condition by the current version of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM).
The condition was commonly referred to as ADD until 1987, when “hyperactivity” was added to the name in the third edition of the DSM. When the revised, fourth edition of the DSM was published in 1994, ADHD was divided into specific subtypes, taking into account the fact that an individual could be diagnosed with ADHD without having symptoms of hyperactivity, according to research published in the journal ADHD Attention Deficit and Hyperactivity Disorders.
There are three forms — or “presentations” — of ADHD, as described in the fifth edition of the DSM (DSM-5), published in 2013, according to an article published in Neuropsychiatry (London).
1. Predominantly Hyperactive-Impulsive
People with this type of ADHD mostly struggle with hyperactivity and impulsiveness, though they may also have some symptoms of inattentiveness.
Hyperactivity can manifest as constant movement and excessive fidgeting and talking. In adults, this may take the form of exaggerated restlessness and an activity level that other people find tiring, according to the National Institute of Mental Health (NIMH).
Impulsivity often takes the form of making important decisions and taking action without thinking through the consequences, especially when those actions might be harmful or detrimental and the resulting effects long lasting.
Impulsivity is also marked by a desire for instant gratification. In social situations, an impulsive person might interrupt others to an extreme degree, and be quick to grow impatient, frustrated, or angry, NIMH experts say.
2. Predominantly Inattentive
People in this category mainly have symptoms of inattentiveness, though they may also have some problems with hyperactivity and impulsiveness. This form used to be — and sometimes still is — called ADD.
Inattentiveness is characterized by struggling to stay focused, being easily distracted from the task at hand, having a hard time with attention to detail, and a lack of organization, according to Children and Adults With Attention Deficit/Hyperactivity Disorder (CHADD). This can result in professional and personal difficulties because of a lack of attention to detail and an inability to make important deadlines, meetings, and social functions.
3. Combined Hyperactive-Impulsive and Inattentive
People in this group have symptoms of hyperactivity, impulsiveness, and inattentiveness. Most children have the combined type, but the most common symptom of ADHD in young children is hyperactivity, NIMH experts say.
Children who are hyperactive may talk excessively, squirm and fidget, and have trouble sitting still. In childhood, impulsivity can take the form of impatience, disruptiveness, and difficulty waiting for a turn. Inattention can include daydreaming, difficulty following instructions, forgetfulness in daily activities, and trouble focusing.
In adults, ADHD symptoms may take the form of:
- Frequent interrupting
- Inability to concentrate
- Lack of organization and follow-through
- Difficulty meeting deadlines
- Frequent mood swings
- Difficulty coping with stress
Learn More About ADHD Symptoms
Causes and Risk Factors of ADHD
Experts aren't sure what causes ADHD. As with most mental health conditions, it is thought to be an interplay of biological, social, and psychological factors, according to CHADD.
Neuroimaging studies using magnetic resonance imaging (MRI) scans to look at brain structure have found that certain neural circuits in the brain are associated with ADHD. These circuits are related to sustained attention, control of inhibitions, motivation, and regulation of emotions, suggests research published in the Lancet Psychiatry.
Not all people with ADHD show the same circuits or changes in circuits, but certain brain differences are more common in people with ADHD than those without it.
Several factors may increase a child's likelihood of developing ADHD.
Current evidence suggests ADHD has a genetic component — meaning it seems to run in some families, according to the aforementioned research published in the Lancet Psychiatry.
The specific genes associated with ADHD have not yet been identified. Scientists believe multiple genes may be involved because of the complexity of the condition, say experts at the National Human Genome Research Institute. These genes may have to do with the processes of certain neurotransmitters, or chemical messengers in the brain, such as dopamine, which plays a role in the brain’s reward systems and in regulating impulsivity and movement.
Environmental Exposure to Toxins and Chemicals
Exposure to substances, especially lead, may be a contributing factor. Studies have indicated a relationship between ADHD and levels of lead in the bloodstream. One study, published in the Journal of Child Psychology and Psychiatry, found that lead exposure was associated with the impulsivity-hyperactivity combined type of ADHD, but not the inattentive type.
Although research has consistently shown a connection between lead exposure and ADHD, it’s important to note that it’s not the only cause of ADHD, nor does lead exposure guarantee that a child will develop ADHD.
Other environmental toxins, such as bisphenol A (BPA) and phthalates, have more recently been found to be potentially problematic for brain health. But the connections between these toxins and ADHD have not yet been established.
Alcohol or Tobacco Use During Pregnancy
Using tobacco during pregnancy has been associated with ADHD symptoms in children in a number of studies. But more recent research has questioned whether substance use directly causes ADHD.
A study published in the Journal of Child Psychology and Psychiatry found no evidence that smoking during pregnancy directly causes ADHD. Another study, published in October 2017 in the International Journal of Epidemiology, found that alcohol use during pregnancy was weakly, though perhaps causally, associated with reported ADHD symptoms but not with clinical diagnoses of ADHD.
Still, pregnant people should refrain from alcohol consumption and smoking because of other well-established risks, including premature birth, low birth weight, and fetal alcohol syndrome.
Traumatic Brain Injury (TBI)
TBI in early childhood has been linked to the development of psychiatric disorders. Among those disorders, ADHD is the most common, with a prevalence of about 20 percent, notes a study published in the May 2018 issue of JAMA Pediatrics. TBI is not uncommon — nearly three million Americans seek emergency treatment for it each year.
Premature Birth or Low Birth Weight
Some research has suggested that the lower a baby’s birth weight or the earlier their birth is, the greater the risk they have of developing ADHD. A meta-analysis and review of 34 studies, published in January 2018 in Pediatrics, confirmed this, showing an even stronger association with the development of ADHD when birth weight was extremely low or the birth was extremely preterm (before 28 weeks).
Diet and Behavioral Factors
Too much sugar or food additives in one’s diet and excessive screen time (television, smartphones, tablets, and computers) have been associated with ADHD. For instance, one small study published in January 2022 in BMC Pediatrics suggested that certain eating patterns, such as high sugar consumption, were more common in children with ADHD than in those without ADHD.
While these factors may affect or exacerbate symptoms, research doesn't support claims that they cause ADHD.
How Is ADHD Diagnosed?
Although many people lose focus, get distracted, and act impulsively on occasion, these behaviors are more severe and more frequent for people with ADHD. Without proper identification and treatment, these behaviors negatively affect their quality of life, whether it’s at work, school, or home.
There’s no single ADHD test used to diagnose the disorder, according to CHADD. A thorough evaluation by a professional — such as a psychologist, psychiatrist, pediatrician, or clinical social worker — is necessary for a proper diagnosis, which rules out other conditions and considers possible coexisting conditions.
The process involves several steps, and your healthcare provider may perform a full medical exam and get a detailed medical history, as well as conduct interviews with family members to gather an in-depth personal history, according to CHADD.
The DSM-5 requires that ADHD diagnoses include the severity of one’s condition, from mild to moderate to severe, because severity can vary throughout one’s life, according to CHADD.
Diagnosing ADHD in Adults
Adult ADHD can cause problems with relationships, work performance, and self-esteem. Many adults with ADHD don't know they have it; they may only know that everyday tasks are challenging. Symptoms can change over time. Some people notice that their symptoms improve as they age, while others continue to struggle.
According to Russell Barkley, PhD, a retired former clinical professor of psychiatry at the Virginia Commonwealth University Medical Center in Richmond, ADHD symptoms arise in a set of mental abilities called the executive functions.
The executive functions encompass a range of processes in the brain, mostly in the frontal areas, that control and manage other brain activities that allow us to get work done — whether it’s creative or more routine; to set and achieve goals; and to take into consideration the potential consequences of our actions and regulate our behavior.
Dr. Barkley, the author of Attention Deficit Hyperactivity Disorders: A Handbook for Diagnosis and Treatment, among many other books, breaks this down into several areas, including self-awareness, inhibition or self-restraint, working memory (meaning actively keeping in mind what you are supposed to be doing in order to achieve a goal or complete a task), time management, emotional self-control, self-motivation, and planning or problem-solving.
Prognosis of ADHD
The long-term prognosis of ADHD depends on whether a person is being treated with medication, behavioral or talk therapy, or both.
In a meta-analysis published in BMC Medicine, researchers looked at more than 351 studies in areas such as academic performance, antisocial behavior, addictive behavior and drug use, self-esteem, and social function. They found that without treatment, people with ADHD had worse outcomes in all categories compared with people without ADHD. Investigators found that treatment for ADHD produced better long-term outcomes compared with untreated ADHD, though not usually to the levels of people without the condition.
Notably, people with ADHD have a significantly increased risk of early death compared with people without the condition, according to a large Danish study published in the Lancet. Early deaths were largely driven by unnatural causes, namely accidents, the researchers wrote.
Duration of ADHD
ADHD persists in 50 to 60 percent of adults who were diagnosed as children, including adults in partial remission, according to research published in the Journal of the American Academy of Child and Adolescent Psychiatry.
Estimates are based on several large prospective long-term follow-up studies, but much of the research does not use the same criteria to determine diagnosis and rates of persistence and remission, which makes it difficult for experts to determine the precise number of people who have shown remission, according to an article published in the Journal of the Canadian Academy of Child and Adolescent Psychiatry.
Treatment and Medication Options for ADHD
There's no cure for ADHD, but a comprehensive treatment approach can help people manage their symptoms and thrive. ADHD treatment usually involves medication, certain behavioral strategies, and lifestyle changes intended to help with focus and organization.
For children ages 4 to 6 years old with ADHD, the American Academy of Pediatrics (AAP) recommends behavioral therapy as a first-line treatment, before medication. Medication is recommended for children age 6 and older.
The most common medications used to treat ADHD include stimulants, nonstimulants, and sometimes antidepressants.
People with ADHD may also benefit from counseling — especially behavioral therapy — to improve behaviors and social skills. Parents and other family members may participate in counseling to develop strategies to support their loved one with ADHD and navigate challenges.
In addition, certain lifestyle changes and accommodations can help create a better environment for people with ADHD. These include:
- Routines and schedules
- Reorganization of your home or workspace
- Physical reminders of tasks at hand
- Removal of distractions
Stimulants are the most commonly prescribed type of ADHD medication, according to the Cleveland Clinic. Often used to improve focus and block out distractions in people with ADHD, stimulants are considered the most effective class of ADHD drugs, improving symptoms in 70 to 90 percent of people, say Cleveland Clinic experts.
Nonstimulant medications can be used for ADHD in people who haven’t had success with a stimulant medication or who can’t take stimulants, according to the Cleveland Clinic.
ADHD medications are available in different formulations: short-acting, intermediate-acting, and long-acting. These drugs can have side effects such as suppressed appetite, difficulty sleeping, and irritability, according to the Cleveland Clinic. A doctor can determine which medication for ADHD is best, describe possible side effects, and explain the pros and cons of medication treatment for ADHD in general.
Complementary and Integrative Therapies
Although there are many different types of supplements and diets people have tried for ADHD, most don’t have enough scientific evidence for experts to recommend using them. Always check with your doctor before trying a new diet or supplement, because it could interact with ADHD medications and cause unwanted side effects or other health problems.
According to the AAP, the following complementary and integrative therapies are not supported by scientific evidence and are not recommended for the treatment of ADHD:
- Megavitamins and mineral supplements
- Anti-motion-sickness medication (intended to treat the inner ear)
- Candida yeast infection treatment
- Electroencephalogram (EEG) biofeedback (training intended to increase brain wave activity)
- Applied kinesiology (intended to realign bones in the skull)
- Decreasing sugar consumption
- Optometric vision training
Learn More About Treatment Options for ADHD
Prevention of ADHD
Although genetics are thought to be one of the main risk factors for ADHD, there are a few health behaviors that may reduce the likelihood that a child will have the disorder, according to the Mayo Clinic.
- During pregnancy, avoid any activities or substances that could harm the development of the fetus. Examples include alcohol, smoking, and recreational drugs.
- Children should be protected from pollutants and toxins such as lead paint or cigarette smoke.
- Although a direct link between screen time and ADHD has not been established, experts recommend limiting the amount of TV and video games in the first five years of life.
Complications of ADHD
Untreated ADHD can lead to several emotional and physical complications, according to Mayo Clinic experts, including:
- Poor self-esteem
- Accidents and injuries
- Substance abuse
- Delinquent or risky behavior
- Trouble interacting with peers and relationship difficulties
Research and Statistics: Who Has ADHD?
ADHD affects nearly 9 percent of school-age children. According to the Centers for Disease Control and Prevention (CDC), 11.7 percent of American boys and 5.7 percent of girls have been diagnosed with ADHD.
ADHD is more frequently diagnosed in boys, but research suggests that it may be underidentified and underdiagnosed in girls.
Research published in the journal BMC Psychiatry noted that girls more often present with the inattentive subtype of ADHD and that their behavior may sometimes be characterized as less outwardly disruptive. That may be one reason why many girls and women don’t receive a proper diagnosis until they’re adults, according to CHADD.
ADHD affects more than 4 percent of adults in the United States, according to the NIMH. But that statistic includes only adults who have been formally diagnosed, so the actual number is likely much higher.
Racial Disparities in ADHD
Research has revealed racial and ethnic disparities when it comes to the diagnosis and treatment of ADHD.
A study published in Pediatrics that examined rates of ADHD diagnosis from kindergarten to eighth grade showed that Hispanic children were 56 percent less likely to be diagnosed with ADHD than white children, and Black children were 36 percent less likely to be diagnosed than white children. Children of other races and ethnicities were 48 percent less likely to be diagnosed with ADHD than white children.
Investigators also found that Hispanic and African American children, as well as children of other races and ethnicities, were much less likely than white children to use prescription medication for the disorder.
Another study, published in March 2021 in JAMA Network Open, yielded similar findings. Researchers found that Black, Hispanic, and Asian children were significantly less likely to be diagnosed with ADHD or receive treatment than white children.
ADHD and Related Conditions
More than two-thirds of people with ADHD have at least one other coexisting condition, whose symptoms can sometimes be hard to distinguish from those of ADHD, according to CHADD.
Children with ADHD may be more likely to have:
- Bipolar disorder
- Conduct disorder, a condition characterized by behaviors such as lying, stealing, fighting, or bullying
- Learning disabilities
- Oppositional defiant disorder (ODD), a condition characterized by a pattern of hostile behavior toward authority figures
- Sleep disorders
- Tourette’s syndrome, a neurological disorder characterized by nervous tics and repetitive mannerisms
Resources We Love
From diagnosis to treatment, ADHD poses many challenges for people who have the condition and their loved ones. Fortunately, there are resources available to help navigate life with ADHD. Consider using them to locate a medical expert or coach, and get advice on managing your own condition or parenting a child with ADHD.
Attention Deficit Disorder Association (ADDA)
This worldwide community of adults with ADHD aims to empower members to discover and reach their potential. ADDA offers virtual support groups, professional directories, and volunteer opportunities.
This organization is a nonprofit dedicated to transforming the lives of children and families struggling with mental health and learning disorders through education, research, and care. They offer in-person care at their New York City and San Francisco locations, as well as virtually for residents of California, New Jersey, and New York.
Children and Adults With Attention Deficit/Hyperactivity Disorder (CHADD)
This nonprofit aims to improve the lives of people affected by ADHD. The organization has chapters all over the country that offer support, education, and advocacy.
Learning Disabilities Association of America
This organization’s vision is to create opportunities for success and self-determination for all individuals affected by learning disabilities like ADHD through support, education, and advocacy.
Learn More About ADHD Resources and Terminology