ADHD stands for Attention-Deficit/Hyperactivity Disorder, which is a medical condition that affects how a person pays attention, sits still, and controls their behavior. It is one of the most common neurodevelopmental disorders of childhood and is usually first diagnosed in childhood, but it can also last into adulthood. Symptoms of ADHD include inattention, hyperactivity, and impulsivity. Some people with ADHD mainly have symptoms of inattention, while others mostly have symptoms of hyperactivity-impulsivity. Many people experience some inattention, unfocused motor activity, and impulsivity, but for people with ADHD, these behaviors are more severe, occur more often, and interfere with or reduce the quality of how they function socially, at school, or in a job.

It is important to note that several conditions can mimic ADHD, such as learning disorders, mood disorders, anxiety, substance use, head injuries, thyroid conditions, and use of some medications such as steroids. Therefore, a thorough evaluation is necessary to determine the cause of the symptoms. There is no single test to diagnose ADHD, and many other problems, like anxiety, depression, sleep problems, and certain types of learning disabilities, can have similar symptoms. One step of the process involves having a medical exam, including hearing and vision tests, to rule out other problems with symptoms like ADHD.

Research does not support the popularly held views that ADHD is caused by eating too much sugar, watching too much television, parenting, or social and environmental factors such as poverty or family chaos. Of course, many things, including these, might make symptoms worse, especially in certain people. But the evidence is not strong enough to conclude that they are the main causes of ADHD.

ADHD is considered a chronic and debilitating disorder and is known to impact the individual in many aspects of their life including academic and professional achievements, interpersonal relationships, and daily functioning. It can lead to poor self-esteem and social function in children when not appropriately treated. However, ADHD can be managed with a combination of medication, behavioral therapy, and lifestyle changes.