Sometimes the nose is open and sometimes it is not open, which may be related to acute and chronic rhinitis, allergic rhinitis, nasal polyps and other diseases, or it may be a physiological phenomenon. If you have the above symptoms, we suggest you go to the ENT department of the hospital in time for treatment. 1. Acute and chronic rhinitis: it can be caused by cold, fatigue, low resistance, chronic lesions in neighboring areas. It is often characterized by nasal congestion, burning, dryness, sneezing and runny nose. As a result, the nose may be sometimes open and sometimes closed. 2. Allergic rhinitis: it is caused by exposure to allergens. It can cause nasal congestion, itchy nose, sneezing, runny nose, smell disorder and other symptoms. As a result, the nose may be sometimes open and sometimes closed. 3. Nasal polyps: often induced by allergic reactions, aspirin intolerance and other reasons, often manifested as nasal congestion, runny nose, decreased sense of smell and other symptoms, so there may be symptoms of the nose sometimes open and sometimes inaccessible. 4. Physiological phenomenon: physiological turbinate cycle, normal people on both sides of the lower turbinate mucosa in the volume of blood vessels were alternating and regular contraction and expansion, manifested as the size of the two sides of the turbinate and nasal resistance to the corresponding alternating changes. In prompts constant turning over during sleep, helping to relieve fatigue. The nose sometimes passes and sometimes does not pass may also have other disease causes, such as nasal vestibular cysts and so on. It is recommended to go to the hospital in a timely manner, to clarify the cause of the disease, and then follow the doctor’s instructions for treatment.