Side Effects of Ginkgo biloba

I want to know if there are any possible side effects to Ginkgo biloba?
My wife has started taking it, and about the same time she has been getting a little "stressed out". As thus she wanted to know if that may be a possible side effect for her.

The reported side effects of Ginkgo biloba leaf include mild gastro-intestinal discomfort and headache. Ginkgo biloba leaf is recommended for use in insufficiency of blood circulation to the brain. If your wife does not have this problem, she may feel a side effect from having too much blood circulating to the brain.