What happens to all these ADHD kids when they grow up? ADHD isn't like a cold or the flu--it doesn't just go away all of the time. As a child grows and matures, it is possible that the symptoms lessen, and in some cases adults are able to overcome the disorder, but it doesn't usually just vanish on its own. At least 40-70% of those diagnosed with this disorder as kids will have it persist when they are adults; however, mental health professionals often overlook ADHD symptoms and continue calling their adult patients who suffer from it anxious or depressed, or diagnose them with a personality...