Pruritus is a skin disease in which the patient is consciously itchy without any primary clinical damage. It is one of the common clinical skin diseases, especially in the elderly. Clinically, it can be divided into two types: limited and generalized. With the onset of winter, the number of friends with pruritus is gradually increasing. In the early years of the disease, the majority of the population to the elderly, in recent years, different age groups of winter pruritus can be seen in outpatient clinics. First, why is prone to pruritus in winter When the temperature decreases, the human body to ensure that heat dissipation is reduced, the skin capillary bed is partially closed, the blood flow of the skin is reduced, sweat, sebum secretion is also reduced, the humidity of the skin decreases, manifesting as dry skin, which is prone to itchy skin, the elderly because of the decline in metabolic level, skin atrophy, more prone to pruritus. With the improvement of living standards, people’s concept of hygiene, daily bathing has become a homework that many people must do, especially the white-collar class and infants and young children, and even wash 2-3 times a day. The consequence is that the sebum that was secreted is rarely washed away, the drier the skin is, the more likely it is also to itch. Second, the disease associated with pruritus Pruritus is more complex, mostly believed to be related to certain diseases, such as diabetes, liver disease, kidney disease, etc.; but also with some external factors stimulation, such as cold, warmth, chemical fiber fabrics. 1, visceral disease gastrointestinal, liver, kidney and other visceral organs occur functional or organic disease: especially diabetes, uremia, liver disease patients, often have generalized pruritus; certain tumors such as leukemia, lymphosarcoma, Hodgkin’s disease, mycosis fungoides, and malignant lymphoma patients can also occur pruritus of the skin. 2, neuropsychiatric system disorders: cerebral arteriosclerosis, spinal consumption, neurasthenia can also occur in generalized or restricted pruritus. 3, endocrine disorders: pregnancy, menstrual disorders, ovarian disease or thyroid disease, etc. Pruritus in the elderly may be related to the reduced level of sex hormones in the body. 4, other: such as focal infections, drugs, diet (alcoholism), food allergies and parasitic or fungal infections can cause generalized or restricted pruritus.