Well Lisa, while I have not slept in yet, I am wearing it again today and it does not bother my skin. I tend to not sleep in long undies so not sure I'll ever do that! Itchy is the wrong word. Textured perhaps is a better word, in contrast to my kate that feels like silk on my skin. BUT I have worn it for 2.5 days straight with nothing on under it, so that says something! Thanks so much Lisa for teaching me about layering. I think my ibex, coupled with my old LLbean fleece, silk, and columbia shell, give me every possible combo I'll need! I also plan to bring my goretex bottoms just in case it snows. They too are medium, but that means I can layer them over jeans or dress pants as needed.