Once the night body itchy may mite dermatitis, chronic urticaria, pruritus and other diseases caused by. 1. mite dermatitis: sleeping at night contact with mites on the bedding, resulting in mite dermatitis, lesions for herpes mound or petechiae, on which there are small blisters, and occasionally large blisters, often accompanied by scratches and scabs, there will be a self-conscious itching, which will lead to itchy at night on the body. 2. Chronic urticaria: related to a number of factors, including food, drugs, physical factors, etc., encountered cold, heat can lead to the occurrence of chronic urticaria, sleep at night body surface temperature is low, it is easy to cause an itchy body at night. 3. Pruritus: it is a skin disease that only has skin itching without primary lesions, drinking alcohol, emotional fluctuations, temperature changes can cause itching episodes or aggravation, it is easy to cause an itchy body at night. Itchy body at night may also be caused by other reasons, if the symptoms are delayed, it is recommended to seek medical attention to identify the cause of the disease, the relevant treatment, so as not to delay the condition.