There is always phlegm at the back of the nasal cavity needs to be treated according to its cause, such as sinusitis, nasopharyngitis, bronchitis, etc. Different diseases choose different treatment methods, including general treatment, medication and other ways. 1. Sinusitis: Sinusitis can lead to an increase in secretions, resulting in the phenomenon of always having phlegm at the back of the nasal cavity. The treatment can use saline for local rinsing to keep the nasal cavity clean, and then with glucocorticoid nasal sprays, such as trimethoprim nasal spray, budesonide nasal spray. 2. Nasopharyngitis: Nasopharyngitis can lead to phlegm in the back of the nose, accompanied by pharyngeal mucosal congestion and edema. Clearly bacterial infection can be prescribed antibiotic drugs, such as roxithromycin, amoxicillin, along with saline rinse nasal cavity, improve symptoms. 3. Bronchitis: bronchitis can cause coughing, coughing up phlegm, nasal congestion, runny nose, due to the backflow of nasal mucus can be caused by the phenomenon of phlegm always behind the nasal cavity. Treatment can choose azithromycin, amoxicillin and other drugs anti-infection treatment, at the same time with the phlegm cough drugs, such as aminobromine hydrochloride. There are many reasons why there is always phlegm in the back of the nasal cavity, it is recommended to go to the hospital in time to improve the examination after the symptoms appear, and follow the doctor’s instructions to take standardized medication and treatment, the above drugs should be used under the guidance of the doctor, and should not be used indiscriminately, so as not to lead to adverse consequences.