
I've tried it, and so has one friend of mine.  No known side effects or
risks.  It didn't seem to work for us, but several studies now have 
suggested it does work for many people, so I think it's worth a try.

You can find it in capsule form at health food stores.  Up to six capsules
a day was recommended, if I remember correctly.  It can also be prepared 
as a tea.

Good luck,