Attention-deficit hyperactivity disorder (ADHD)
- Reviewed by Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing
What is attention-deficit hyperactivity disorder (ADHD)?
Attention-deficit hyperactivity disorder (ADHD), usually first diagnosed in childhood, can appear in a variety of forms and has many possible causes. People with ADHD probably have an underlying genetic vulnerability to developing it, but the severity of the problem is also influenced by the environment. Conflict and stress tend to make it worse.
The main features of this disorder are found in its name. Attention problems include daydreaming, difficulty focusing and being easily distracted. Hyperactivity refers to fidgeting or restlessness. A person with the disorder may be disruptive or impulsive, may have trouble in relationships and may be accident-prone. Hyperactivity and impulsiveness often improve as a person matures, but attention problems tend to last into adulthood.
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About the Reviewer

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing
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