Sudden itch on the body when scratching a red, consider the skin scratching disease, belongs to a type of urticaria; may also be contact dermatitis.
1. Skin scratches: most patients can not find the exact cause of the disease, the common causes are food factors, drug factors, infectious factors, as well as mental factors, endocrine factors, physical factors, chronic physical diseases and so on.
The manifestation of scratching or scratching the skin with a blunt instrument, a few minutes after the scratch will appear along the strip-shaped elevation, with or without itching, half an hour can subside on its own. Late-onset cutaneous scars, it is possible that the skin may appear only after a few hours of the wind and edematous erythema, 6 ~ 8 hours to reach the peak, the duration is generally not more than 48 hours.
2. Contact dermatitis: is due to contact with certain exogenous substances, acute or chronic inflammatory reaction occurs in the skin mucous membrane contact area, may be manifested as a sudden itch on the body in contact with the area, a scratch on a piece of red, the typical symptoms will also result in skin erythema, and there are pimples, pimples and other phenomena.
It is recommended to go to the hospital in time for examination, to clarify the cause of the disease, and follow the doctor’s instructions for treatment.