Feeling itchy all over the body at night may be caused by contact with allergens, may be caused by indoor temperature change or air dryness, may also be suffering from some kind of internal disease such as renal insufficiency, etc., and need to be analyzed specifically. 1. Contact with allergens: there may be dust mites or plush fabrics on the bedsheets and bedding, etc. If the patient is allergic to these things, allergic diseases will occur after contact, so the whole body itchy at night, we need to do anti-allergy treatment in a timely manner. 2. Indoor temperature change or air dryness: in the evening after taking off the clothes inside the quilt temperature rises, the air moisture content is less, the skin is drier, can cause physiological itching all over the body. 3. Internal diseases: some internal diseases can lead to itchy skin symptoms, such as renal insufficiency, cholestatic itching, etc., these diseases can stimulate the sensory nerve endings lead to itching. There are many reasons why you feel itchy at night, and patients are advised to go to the hospital in time to have a checkup when this situation occurs, and to treat the symptoms after a clear diagnosis is made. Do not scratch the skin too much, keep the skin clean, you can also use moisturizing skin care products to relieve the symptoms.