The rash appears at night, but if the rash fades completely during the day without leaving traces, consider the possibility of urticaria. Urticaria manifests as an erythematous rash with significant itching, sometimes combined with dyspnea, chest tightness, abdominal pain, diarrhea, and in severe cases, anaphylactic shock, antihistamines can be given orally, and nighttime episodes of urticaria need to be considered as an allergic reaction caused by the intense alternation of heat and cold, dust mites, house dust or indoor flowers, pets, etc. It is recommended to actively remove the triggers. If the rash is more widespread, sometimes glucocorticoid treatment is needed, so it is best to go to a regular hospital and not to treat it yourself. If the rash still does not subside during the day just does not itch, it is also necessary to exclude whether it is scabies, scabies well occurring in the thin and tender parts of the skin, like an eczema-like appearance.