Itchy anus at night may be due to parasites, hemorrhoids and other causes of the situation, but also may be a symptom caused by perianal eczema. 1. Parasites: when the patient consumes unclean food, or perianal hygiene is not clean, the body’s immunity is poor, etc., may be infected by pinworms and other infections, may appear at night anal itching. 2. Hemorrhoids: hemorrhoids lead to incomplete anal closure, if the patient does not pay attention to perianal hygiene, resulting in repeated stimulation of inflammation, producing a large amount of secretion, there may be a significant itching at night. 3. Perianal eczema: If the patient’s skin cleanliness is poor, friction, wounds, or eat allergic, irritating food, etc., may appear perianal eczema, which leads to the symptoms of anal itching at night. Patients with itchy anus should pay attention to clean perianal hygiene in daily life to reduce bacterial growth, and seek medical treatment in time to give treatment when symptoms worsen.