Phlegm in the throat may be caused by chronic pharyngitis, chronic rhinitis, chronic bronchitis and other reasons. 1. Chronic pharyngitis: inflammation stimulates the mucous membrane of the throat to become congested and edematous, lymphoid follicle hyperplasia, leading to exuberant secretion of the glands in the throat so that the glandular secretion increases and gathers into phlegm, which results in the situation of phlegm in the throat all the time. 2. Chronic rhinitis: chronic inflammatory stimulation of the nasal mucosa and submucosa, leading to inflammation of the nasal mucosa backflow into the throat, there is always phlegm in the throat. 3. Chronic bronchitis: viruses, bacterial infections, air pollution and other causes of chronic bronchitis, resulting in excessive secretion of mucus cells in the airway to appear a large amount of phlegm, the excretion of phlegm into the pharynx appears in the throat all the time. Patients can be under the guidance of the doctor for expectorant, asthma, anti-infection and other treatments, daily attention to a light diet, the treatment period is recommended to quit smoking and alcohol.