ADHD symptoms often include an inability to focus, disorganization, and restlessness. Adults with ADHD may have a hard time organizing things, listening to instructions, remembering details, or difficulty completing tasks, which can affect their relationships at home, school, and work.
People who have ADHD may exhibit different symptoms, and they may experience them at different levels of severity, ranging from mild to significant impairment.
Proper diagnosis relies on a comprehensive clinical evaluation by a health professional, who will take into account personal history, self-reported symptoms, and mental-status testing, as well as early development problems and symptoms of inattention, distractibility, impulsivity, and emotional instability. More on Adult ADHD from the Anxiety & Depression Association of America.