Lying down without coughing up cough may be environmental stimulation, nervousness and other physiological factors, or consider the allergic cough, cough variant asthma and other diseases. 1. Physiological factors: when the air contains irritating gases, cigarettes, dust mites and other components, get up and inhale such gases, may stimulate the local mucous membrane, the symptoms of cough. Or it may be caused by nervous tension. This kind of situation is a normal phenomenon, no need to worry. 2. Allergic cough: the cause of allergic cough is not yet clear, it may be caused by oil smoke, dust, cold air, cigarette smoke and other factors. Patients may have paroxysmal, irritating dry cough, which may occur when inhaling irritating components in the air. 3. Cough variant asthma: The cause of cough variant asthma may be genetic, physical changes, pollen, oil smoke and other factors. Patients may experience symptoms such as coughing, wheezing, chest tightness, etc. Some patients may exhibit coughing when lying down without coughing up. There are many reasons that lead to coughing when lying down without coughing, and it is recommended that patients promptly identify the cause of the disease, cooperate with the doctor to improve the examination, and actively treat the disease.