The symptoms of phlegm in the throat are mainly related to the chronic inflammatory diseases of the mucous membrane in the throat. Patients may use their voices too much in their work and life, or they may smoke, drink, eat spicy and stimulating food, or be exposed to air pollution. Inflammatory secretions stick to the local mucous membrane surface of the throat and produce the symptoms of phlegm in the throat. Patients may have different degrees of lymphatic follicular hyperplasia in the back wall of the throat, which may also lead to similar symptoms. Some patients may also have a certain degree of acute and chronic inflammation of the nasal cavity and sinuses, and the inflammatory secretions from the nose may flow backward into the throat repeatedly, which may also cause phlegm in the throat.