There are many reasons for a strong cough with phlegm before going to bed at night, which is commonly associated with cough variant asthma, cardiac insufficiency, gastroesophageal reflux disease and so on. 1. Cough variant asthma: it is a special type of asthma, which can be treated with inhaled glucocorticosteroids (e.g. budesonide) and bronchodilators (e.g. salbutamol) under the guidance of a doctor. 2. Cardiac insufficiency: some patients with chronic cardiac insufficiency, lying down at night, there will be an increase in the volume of return blood, increased cardiac load, aggravated pulmonary stasis, causing coughing, accompanied by dyspnea, coughing up pink foamy sputum, you can take a sitting position, the symptoms can be alleviated, but it is necessary to consult the doctor in a timely manner. 3. Gastroesophageal Reflux Disease (GERD): When lying down, the acidic reflux material may reflux into the throat, irritating the throat and trachea, causing night cough and pharyngeal discomfort. Omeprazole and domperidone can be used under the guidance of a doctor so as to reduce coughing. There are many reasons for strong cough with phlegm before going to bed at night, you should go to the hospital in time to clarify the cause of the disease, under the guidance of the doctor to avoid delaying the condition.