There are several cases of coughing in the middle of the night: First, the problem of phlegm discharge at night, because during the day, the respiratory tract wants to discharge phlegm from inside the lungs all the way to the mouth and nose, especially from the bottom of the lungs all the way up to the mouth, which is a vertical process that is more troublesome and not easy to discharge, but when the body lies flat during sleep, the airway becomes horizontal from bottom to top, and phlegm will be easier to discharge in this case. Second, at night when you eat dinner taste heavier, or after dinner ate some snacks, like plums, strange beans, or ate something more taste heavier, resulting in less water inside the airway, eat heavy taste, a little thirsty, less water in the night breathing, because the breathing during sleep are deeper and larger, resulting in the dry air outside constantly stimulate the airway and throat, will also trigger a cough. This situation in the room generally to humidify, after dinner on try not to eat some taste heavy, there is a better way, is to drink a glass of hot milk before going to bed, milk is very good lung moistening effect. Third, the case of nighttime allergies, because there are many mite debris on the bedding, these things are a strong allergen. If one has allergies, coughing at night can trigger an allergic cough due to the excessive accumulation of these mite debris. So this situation should be dried more bedding, knocking, try to drain mites, you can also use a mite remover.