ADHD, or attention-deficit/hyperactivity disorder, is a developmental disorder that is characterized by inattention, impulsivity, and, in some cases, hyperactivity. The symptoms of ADHD can interfere significantly with an individual’s daily activities and relationships. The symptoms of ADHD can be categorized into two types of behavioral problems: inattentiveness and hyperactivity-impulsivity.

The following are the most common symptoms of ADHD:

Inattention:

• Short attention span for age (difficulty sustaining attention)
• Difficulty listening to others
• Difficulty attending to details
• Easily distracted
• Forgetfulness
• Poor organizational skills for age
• Poor study skills for age

Impulsivity:

• Often interrupts others
• Blurts out answers before questions have been completed
• Difficulty waiting for his or her turn
• Frequently interrupts or intrudes on others
• Takes unnecessary risks

Hyperactivity:

• Fidgeting with hands or feet or squirming in seat
• Leaving seat often, even in situations when remaining seated is expected
• Running or climbing at inappropriate times
• Difficulty playing quietly
• Always seeming to be "on the go"
• Talking excessively

It is important to note that ADHD symptoms can change over time and can be different in boys and girls. Adult symptoms of ADHD also tend to be far more subtle than childhood symptoms. Some specialists have suggested the following as a list of symptoms associated with ADHD in adults:

• Carelessness and lack of attention to detail
• Continually starting new tasks before finishing old ones
• Poor organizational skills
• Inability to focus or prioritize
• Continually losing or misplacing things
• Forgetfulness
• Restlessness and edginess
• Difficulty keeping quiet, and speaking out of turn
• Blurting out responses and often interrupting others
• Mood swings, irritability, and a quick temper
• Inability to deal with stress
• Extreme impatience
• Taking risks in activities, often with little or no regard for personal safety or the safety of others

It is important to note that other problems, like sleep disorders, anxiety, depression, and certain types of learning disabilities, can have similar symptoms. Therefore, if you are concerned about whether a child or adult might have ADHD, the first step is to talk with a healthcare provider to find out if the symptoms fit the diagnosis.