Lying down and coughing is generally these kinds of situations, as follows: first, previously had a respiratory infection disease, and then well after the lungs of the phlegm is not completely clean. The phlegm will move upward when lying down and stimulate the mucous membrane of the airway through the trachea to trigger a cough. This situation needs to be followed by phlegm-cleansing medicine, or herbal medicine, which cleanses the remaining heat and cleanses the remaining evil, helping to cleanse the lungs so that it does not reappear. Second, people with allergy symptoms, just like variant asthma, cough, chronic cough or allergic cough, may be allergic to mites, dust mites, or lint or cotton fiber. This time when you are lying down, the body to the sleeper squeeze will lead to a large number of airflow to the debris deposited inside to the air, and we lie down just inside the large dust haze field, may trigger a cough after lying down. Third, the indoor environment is too dry, lack of water, the mucous membrane of the respiratory tract at this time, because when lying down, when people want to sleep breathing will become deeper and deeper, more and more, so as to enter the sleep state. When increasing breathing, the environment is particularly dry on the airway or irritation, so the room should be properly increased humidity to avoid.