Itchy skin all over the body may be due to dry skin, temperature changes, exposure to allergens and other factors. 1. Dry skin: This is a common cause of generalized itchiness. Elderly people may suffer from dry skin because of skin aging or reduced sebum secretion. Of course, frequent bathing or the use of alkaline skin care products can also cause dry skin, which in turn produces itchy symptoms. 2. Temperature changes: factors such as too hot a blanket, sudden exposure to heat or cold may stimulate the onset of itching. 3. Contact with allergens: For people with allergies, contact with allergens may trigger a perverse reaction in the skin, resulting in itchy skin all over the body. Itchy skin, there may be other reasons, need to cooperate with the doctor to determine the cause, and then do targeted treatment.