Adult ADHD ADHD (attention deficit hyperactivity disorder) is one of childhood’s most common neurodevelopmental disorders, affecting nearly 11% of US children between the ages of 2 and 17. Symptoms of ADHD tend to improve with age because many kids become better at self-regulating as they get older. But contrary to popular belief, ADHD doesn’t go away when a person becomes an adult; in fact, ADHD is considered a lifelong condition, with many individuals actually receiving a first diagnosis well into...