A wide range of conditions can cause an itchy neck—such as eczema, psoriasis, and diabetes. This itchiness is medically also known as pruritus. An itchy neck usually isn’t a sign of anything serious ...
About one-quarter of people with roseola develop a flat, spotty, reddish rash after the fever goes away. It first appears on the chest, back, and belly, and then spreads to the neck and trunk.