Most of the time, phlegm in the throat cannot be coughed out because the internal heat has not been resolved, and the inflammation in the lungs is called internal heat in Chinese medicine. If you only use phlegm and cough medicine without clearing the heat in the lung, the phlegm will stick to the organism very strongly, so it is not easy to be expelled. There is another situation where the phlegm is inside the lung, because the lung is not active enough, this situation is called lung qi deficiency, and when the lung qi is deficient, it is difficult to get the phlegm out of the lung, at this time, you can actively increase the breathing volume to help expel the phlegm, and you can also use medicine to help expel the phlegm by supporting the righteousness and dispelling the evil. The other condition is the patient with Yin deficiency, the patient with Yin deficiency has a dry airway and thin mucous membrane, at this time it is also difficult to expel phlegm if there is phlegm, so it is necessary to nourish Yin and clear the lung to help expel phlegm.