How does skin rise a knot itch to return a responsibility

Many skin diseases can cause pimples on the skin accompanied by itching, among which the most common ones are urticaria, eczema, etc., as follows: First, urticaria is also called wind pimples, and its manifestation is pink or light red on the skin. Whirls, accompanied by very severe itching, are caused by various internal and external factors, which cause skin capillaries to dilate and increase permeability, so the skin shows localized edema, so the skin shows wheals. The second is eczema, which is caused by various internal and external factors of an allergic reaction to the skin, more common are food, inhalants, environment, etc. Eczema rash and wind lumps are a bit different, belonging to symmetrical, smaller, pleomorphic rash, while eczema also has a characteristic thing is easy to form skin blisters, exudates, some wet.