What's the difference between a child with attention-deficit hyperactivity disorder (ADHD) and one who is simply more active than other children?

Many children are rambunctious, to an extent that their parents or teachers find somewhat worrisome. Figuring out how to distinguish between normal high-energy levels and pathological overactivity can be quite difficult. Furthermore, the distinction can be complicated by parental tendencies to be permissive and to fail to set up clear rules, reprimands, or restrictions for when a child steps outside the limits.

Figuring out how to make this distinction is not a trivial issue. Children diagnosed with ADHD are usually prescribed methylphenidate (Ritalin) or other medications that lessen their activity ...