I have FMS but am asking this question for a friend of mine with CFS. I realize there are many similarites but at the same time, there are differences. She seems to be experiencing many episodes of vertigo and I was just wondering if this is a common complaint of CFS? I do know it is fairly common with FMS but does anyone here have it? Her doc first thought it was being caused by a virus but since it has continued, they may be backing off of that theory. I'd appreciate any input--thanks.