If the cough is triggered by a dry throat in the middle of the night, it is very likely that the environment is dry and there is also a cough caused by Yin deficiency and internal heat, because if there is phlegm and cough, as soon as you lie down, you will want to cough, usually the cough is caused by the discharge of phlegm. However, if the cough starts after midnight, most of the coughs are caused by Yin deficiency and heat in the body. If the disease is not completely healed, that is, if the lung disease is not completely healed, it will go to the yin part, hide in the yin part and not develop during the day, and then at night when the yin part is set, it will run out, and at this time it is especially easy to have a dry throat and cough after midnight. The treatment should be to nourish Yin and clear heat, not to relieve heat from the surface or to clear heat from phlegm, which is a special way to clear heat.