itching

I have had a problem with itching. It started about 6 weeks ago. The soles of my feet and the palms of my hands started itching, with no visable reason (no dry skin, no rash). Now it sometimes includes my ankles and my legs. I know the problem isn't "in my head" (I'm happy, well-adjusted and relatively stress-free) but this itching is about to drive me crazy! I hope someone can shed some light on this.