Skin red rash may be due to mosquito bites, contact dermatitis or eczema and other causes, according to different situations to take a cold compress or apply symptomatic drugs or oral medication and other ways of treatment. 1. Mosquito bites: mosquito bites the human body, subcutaneous tissue stimulation, will cause local capillary dilation, the blood of the tissue fluid exudes to the blood vessels outside the inflammatory reaction, so there is a red rash. You can carry out local cold wet compresses, which can inhibit cellular activity and slow down the conduction of nerve impulses, thus relieving the symptoms. 2. Contact dermatitis: allergy susceptibility to contact with allergenic substances may lead to increased permeability of the skin tissue, so that the skin appears to be localized congestion and the formation of red rashes. Glucocorticoid ointment such as dexamethasone can be applied locally for treatment, which can effectively relieve the symptoms of red skin rash. 3. Eczema: mainly due to internal and external factors together, too much spicy and irritating food is also easy to aggravate the condition, resulting in red skin rashes. You can apply zinc oxide ointment and other medications, and if necessary, use glucocorticoid drugs, such as dianabed ointment, hydrocortisone butyrate ointment, etc., which can effectively alleviate the symptoms. If necessary, you can also take oral loratadine and other drugs anti-allergy drug treatment. If there is a red rash on the skin, we should go to the hospital in time to clarify the cause, and then carry out targeted treatment, and at the same time pay attention to maintain a light diet to avoid aggravation of the situation. The above drugs need to be standardized use under the guidance of a doctor.