Sudden red patches on the body may be urticaria, pityriasis rosea, psoriasis, etc. They can be treated by topical medication and systematic medication.
1. Urticaria: acute spontaneous urticaria is more common, usually conscious of itching, and itchy parts can appear red spots, wind masses. You can choose glycerine lotion, etc.; in mild cases, you can use loratadine, levocetirizine hydrochloride and other drugs for treatment; in severe cases, you can use dexamethasone, methylprednisolone and so on.
2. pityriasis rosea: it is self-limiting, local glycerine lotion, hydrocortisone and other drugs can be used; itchy people can use loratadine and other anti-allergic drugs; ultraviolet irradiation can also shorten the process.
3. Psoriasis: mild psoriasis can use hydrocortisone, prednisone and other drugs, or choose all-trans retinoic acid cream, carbotriol, tacrolimus and so on for treatment; severe cases need to use methotrexate, cyclosporine and so on; in addition to this, you can also consider the biological agents, photochemotherapy and so on.
Sudden red patches on the body, it is recommended to go to the hospital for examination, to clarify the cause of the disease, under the guidance of the doctor for drug treatment.