Small red spots on the body that are particularly itchy can often be caused by several diseases, such as papular urticaria, mites, dermatitis, scabies, chicken pox, etc. Papular urticaria is often caused by mosquito bites and often occurs on the side of the limbs, manifesting itself as a windbag-like papule with small blisters, often accompanied by intense itching. Mite dermatitis is mainly caused by erythema, papules, etc., accompanied by itching, on the part of the skin in contact with clothing and bed sheets that have not been cleaned for a long time. Scabies is a parasitic infectious skin disease caused by the scabies mite, and is often seen as red papules and nodules on thin skin areas, such as the armpits, groin, and scrotum. Especially at night with intense itching, the patient often scratches because of scratching.