Coughing hard in bed at night clinically refers to nocturnal coughing and has many causes. This may be caused by temperature, diet, allergies and other external stimuli; it may also be caused by respiratory disease, pleural disease, cardiovascular disease and other pathologic factors, and should be promptly consulted to identify the cause of the disease. 1. External factors: If there are dust mites, pollen, animal dander and other inhalants in the surrounding environment when sleeping, it is easy to induce night cough, so we should pay attention to keep the environment clean and comfortable when sleeping at night. Cold and improper diet are also easy to cause night cough, so you should avoid eating allergic foods and pay attention to keeping warm. 2. Pathologic factors (1) Respiratory diseases: night cough is often associated with respiratory tract infections, such as upper respiratory tract infections, pharyngolaryngitis, bronchitis, pneumonia patients are often accompanied by symptoms of night cough. (2) Pleural diseases: pleurisy, pleural effusion, spontaneous pneumothorax or thoracic puncture can also cause nocturnal cough. (3) Cardiovascular diseases: when mitral valve stenosis, left heart failure cause pulmonary stasis or pulmonary edema, due to plasma or bloody exudate in the alveoli and bronchial tubes, it can also cause night cough. If the symptoms of nocturnal cough cannot be improved after adjusting external factors, it should be taken seriously, and the patient should consult a doctor in time to give targeted treatment after a clear diagnosis.