Eczema is a skin disease that first appears as an itchy, red rash. Eczema can appear anywhere on your body and makes it uncomfortable to perform normal daily activities. Worst of all, the more you scratch the rash, the worse it gets. Many people with eczema get rashes on their elbows or behind their knees, but it is also not uncommon to find it on the neck, wrists and ankles. Eczema is very common among infants and children; most people who suffer from eczema will first experience it before they turn five years old. Eczema tends to come and go without warning, making it an irritating and unpredictable disease.