When blockage of the nasopharynx occurs, it can cause local symptoms of the ear, nose, pharynx and throat. Outward blockage of the pharyngeal opening of the eustachian tube can lead to obstruction of ventilation and drainage in the middle ear, which can be complicated by secretory otitis media, causing symptoms of hearing loss and tinnitus, and sometimes purulent otitis media, leading to severe pain in the ear and pus flowing from the external ear canal. When the posterior nostril is blocked forward, it can be complicated by rhinitis and sinusitis, resulting in nasal congestion, runny nose, etc. It can also lead to an occlusive nasal sound when speaking, severe snoring during sleep, and open-mouth breathing. The blockage of the nasopharynx can lead to secretions that irritate the respiratory tract downward, thus causing throat and lower respiratory tract symptoms, mainly paroxysmal cough, and in severe cases, also complicated by bronchitis. If there is prolonged open-mouth breathing, especially in children, it can also affect the abnormal development of facial bones and teeth.