Generalized skin itching can be divided into physiological and pathological causes. Physiological causes such as the weather is too dry, the skin lack of moisture; pathological causes such as cholestasis, diabetes and so on. 1. Physiological causes: the weather may be too dry, the skin lack of moisture, may cause skin itching, mostly in winter or the elderly lack of sebum, can also cause generalized itching. 2. Pathologic causes: (1) Cholestasis: itching is a common clinical manifestation in patients with liver disease and cholestasis. The exact substance causing the itching is not known, and it is thought to be due to bile acids in the blood or skin. (2) Diabetes mellitus: Diabetes mellitus can also cause itching of the skin, which can be generalized throughout the body and more often limited to the perianal and genital areas. It may be caused by neuropathy, Candida infection, and dry skin. Causes of generalized itchy skin for more reasons, in the exclusion of physiological factors, it is recommended to go to the regular hospital to clarify the cause of the disease.