Attention-deficit/hyperactivity disorder (ADHD) is a chronic mental health condition that makes it challenging for children and adults to focus on tasks, pay attention, control impulsive behavior and even to sit still. These challenges often prevent children from functioning well in school and getting along with family members at home. Symptoms of hyperactive or impulsive ADHD include fidgeting or squirming, trouble playing quietly and excessive talking and interrupting. Symptoms of inattentive ADHD are making careless mistakes, being easily distracted, difficulty following instructions and forgetfulness.