Nasal congestion after a cold is mostly caused by congestion of the nasal mucosa and other reasons. Colds can be triggered when the body’s resistance drops and it is attacked by a variety of viruses such as parainfluenza virus, adenovirus or rhinovirus. The disease will cause irritation and inflammation in the nasal cavity, resulting in congestion of the nasal mucosa, which will affect the normal exchange of gases to a certain extent, causing nasal congestion after a cold. After a cold, most patients in the early stage of sneezing and nasal congestion and runny nose symptoms, with the aggravation of the condition, may also appear nasal mucosa congestion and obvious secretion and other symptoms. Nasal congestion after a cold should pay attention to the timely visit to the hospital, under the guidance of the doctor to choose the appropriate method of treatment with medication.