Because the cotton swab is hard, there are structures such as turbinate and nasal septum in the nasal cavity, and the nasal mucosa is thin, the patient can't see the internal structure of the nasal cavity clearly. If they clean the nasal cavity themselves, it is easy to damage the nasal mucosa, thus causing nosebleeds and infections. If the patient has a lot of nasal secretions, or when the nasal cavity is dry, the nasal cavity can be wetted with seawater nasal spray and cleaned. If there is a large amount of nasal secretions in the nasal cavity, the nasal cavity can be washed with a nasal irrigator. Generally, washing the nasal cavity with normal saline at about 37℃ can reduce nasal secretions, clean the nasal cavity, moisten the nasal cavity and alleviate the symptoms of rhinitis. When the patient has a runny nose, he must not blow his nose hard, so as not to cause otopharyngeal duct infection and secretory otitis media.