Why does meeting skin itch rise a pimple

The symptoms are more common in urticaria, which is a localized edema reaction caused by reactive expansion and permeability increase of small blood vessels in skin mucosa. The etiology of most patients is unknown, especially chronic urticaria. The common causes are as follows: 1. Food, including animal protein, plants and certain food additives. 2. Drugs. 3. Infection, including various bacteria, fungi, viruses, parasites and other infections. 4. Physical factors. 5. Animal and plant factors. 6. Mental factors. 7. Secondary to visceral and systemic diseases. 8. Other factors, inhalants, pregnancy or menstrual cycles.