Attention Deficit Hyperactivity Disorder (ADHD) has always been associated to children's developmental problems. However, in the U.S. alone, WebMD.com states that there are about 8 million adults with this problem and some of them still remain undiagnosed and thus, untreated.The onset of Adult ADHD may have started off in childhood. About 60% of children with ADHD bring the symptoms into adulthood. However, in some cases, symptoms only manifest during adulthood and not as prominent during childhood. Or, it may be that the symptoms were never diagnosed during the childhood years.Grab The book to learn more!