A red rash on the stomach is considered to have the following two possibilities: 1. scabies: it occurs mainly in the area around the umbilicus, with tiny papules and small tunnels drilled by scabies, and the same characteristic rash can be seen between the fingers. A rash like this can appear all around the body, but large nodules can be seen on the buttocks and vulva. This disease is caused by scabies infection, and in terms of treatment, it is necessary to apply sulfur lotion twice a day, and then apply sulfur ointment after the lotion dries in order to kill the scabies. If there is severe itching at night and it is difficult to sleep, you can inject chlorpheniramine maleate injection once a day, once a time 1 ml. 2, contact dermatitis: mainly due to allergic reactions caused by wearing metal jewelry. Treatment can be oral Orotadine hydrochloride tablets, external application of mometasone furoate ointment coated.