One side of the child’s nasal cavity inside a little bit swollen, commonly caused by upper respiratory tract infection, need to be under the guidance of the doctor for targeted treatment, such as drug therapy. Upper respiratory tract infection is usually caused by viral and bacterial infections, inflammation of the upper respiratory tract may cause nasal mucosa congestion and swelling. In terms of treatment, the nasal cavity can be rinsed with saline or sea salt water, and if combined with bacterial infections, antibacterial drugs, such as cefixime, can be applied if necessary. It is important to note that the use of medication should be accompanied by routine blood tests to determine whether the infection is bacterial or viral, which will help in the accurate use of medication in the clinic. However, this symptom alone is not enough to diagnose the disease, and may be caused by other factors, such as nasal cysts and polyps. Parents are advised to bring their children to the doctor for diagnosis and treatment. The above medications should be used under the supervision of a doctor.