Allergic dermatitis itchy at night may be related to the excitation of the vagus nerve at night, the combination of other dermatitis, contact with allergic substances and so on. 1. Vagus nerve excitation at night: the vagus nerve of human body will be in a more excited state at night, so it will be more sensitive to the itching sensation at this time. 2. Combination of other dermatitis: sometimes not simply allergic dermatitis, if the combination of eczema, scabies or other dermatitis, is also prone to night itching symptoms, so pay attention to the body in a timely manner there are no other skin changes, if necessary, we recommend timely access to medical care. 3. Contact with allergic items: some people itch at night, there may also be a relationship with the items that come into contact with the night, such as sleeping covers, shower gel used in the bath, etc. to cause skin itching. If the symptoms of atopic dermatitis itchiness at night continue to be unrelieved or even aggravated, you should consult a doctor in time and follow the doctor’s instructions for treatment.