A recent article in the Los Angeles Times gives the pros and cons on the use of “bipolar disorder” in children through the opinions of two psychiatrists on opposite sides of the controversy.
The problem with using “bipolar” is that it requires a too-loose interpretation of the symptoms seen in adults with bipolar disorder.

That is, the symptoms in children aren’t really like those seen in adults. But while there is disagreement about the label, there is consensus that children with wide mood swings need help. Now it is becoming increasingly clear that children with up-and-down mood probably have some other problem, not bipolar disorder. These children may be described as emotionally “dysregulated,” that is, their brain cannot seem to keep their emotions regulated or stable.

Still, I think that Dr. Gabrielle Carlson gets to the heart of the matter in a quote from the LA Times article:

…In our current climate of insurance reimbursement, doctors cannot spend the time they need to fully diagnose these kids. The problem is that kids are being labeled with something we think we know, and which is lifelong. Child psychiatrists don’t have much time with kids. Then we spend what precious little time we have trying to come up with the “right” diagnosis, even though it probably won’t change the medicine we give. In doing so, we give the child a diagnosis that might last a long, long time.

In the process we ignore a lot of information unrelated to diagnosis that would help tailor a much better intervention — information like how mom and dad are getting along, whether or not the home is safe, whether mom has to work so many hours each day to make ends meet that she has little time for her son, and the like. In most cases, proper treatment for the psychological and social world in which a child lives goes much farther toward helping his behaviors than having the right label on his behavior.

Read More on  http://www.kevinmd.com/blog/2010/06/children-bipolar-disorder.html