A child with ADHD has difficulty to pay attention, control himself or herself, behave, and sit still. The symptoms appear before 12 years of age. While ADHD affects behavior, emotion, learning, and social skills, the exact symptoms vary from person to person. Some children are naughty, unable to sit still and control their behavior. Others find it hard to pay attention and being forgetful in daily activities. ADHD occurs in children around the world and the disorder affects 6 - 9 % of school-aged children in Thailand.

