Large areas of skin flushing for several days do not return, may be related to contact dermatitis, eczema, capillary dilatation and other reasons. 1. Contact dermatitis: if the skin is in contact with allergenic substances such as ointment, it can lead to abnormal autoimmunity of the organism, and the phenomenon of large skin flushing that does not go away for a long time. 2. Eczema: usually first appear skin erythema, on the basis of erythema appear pimples, papules. 3. Capillary Dilatation: Decreased elasticity and increased brittleness of capillaries can lead to persistent uneven dilatation of blood vessels, which can lead to redness of the skin. It is recommended that those who have large areas of redness on the skin that do not recede for several days go to the hospital in a timely manner to clarify the cause of the disease and standardize the treatment under the guidance of the doctor.