The basic principle of rhinology is to use a certain pressure to send physiological saline into the nostril, flow through the nasal vestibule, sinuses and nasal passages, bypass the nasopharynx, or discharge it from one nostril or from the mouth. Through the above path, diseases and dirt accumulated in the nasal cavity are discharged by the impact of water flow, so as to restore the normal physiological environment of the nasal cavity, restore the self-detoxification function of the nasal cavity, and achieve the purpose of protecting the nasal cavity. It's like cleaning a traumatic wound with disinfectant to remove bacteria. Has obvious anti-inflammatory effect.