Coughing before going to bed and not coughing during the day may be caused by environmental discomfort, bronchial dilatation, cough variant asthma and so on. 1. Environmental discomfort: before going to bed, people used to close the door and shut the window, resulting in indoor dryness, air circulation, dry and turbid air stimulation of the throat so that people coughing symptoms. 2. Bronchial dilatation: bronchial is mainly caused by recurrent bronchial septic inflammation, causing abnormal and persistent bronchial dilatation, manifested by chronic cough, sputum, with or without hemoptysis and other symptoms. When a person is lying down before going to bed, it is easy for the phlegm in the lungs to flow into the trachea and then irritate the trachea, making the person cough. 3. Cough variant asthma: allergies, airway hyperresponsiveness or genetic factors can trigger cough variant asthma, often manifested as a persistent dry cough at night when sleeping or early in the morning when waking up. Sleeping cough can be caused by a variety of reasons, if the patient coughing symptoms are more frequent, it is recommended to go to the hospital to improve the relevant examination, clear cause, under the guidance of the doctor to take targeted treatment to treat.