After the baby’s cold is well, most of the blocked nose is due to the symptoms of nasal mucosal swelling after the cold has not disappeared, nasal infection, allergic rhinitis and other reasons. 1. Children with colds can cause swelling of the nasal mucosa, children with narrower nasal passages will appear the symptoms of the nose is not ventilated. The cold is not fully recovered may lead to the existence of such symptoms. 2. Nasal infection: children may cause rhinitis after a cold, nasal turbinate congestion, nasal mucosal hyperplasia. Inflammatory nasal secretions can lead to a lack of airflow in the nose. 3. After a child has recovered from a cold, allergic rhinitis can be caused by contact with allergens. Allergic rhinitis can lead to swelling of the nasal cavity, which can affect the ventilation of the nose. There are many reasons why a child’s nose does not work after a cold, so it is recommended that parents take their children to the hospital for a checkup to determine the cause of the problem and then treat it.