“There are two main clinical causes of unilateral nasal congestion.
One is a deviated septum. The septum is actually the “wall” between the two nostrils. Most people have a deviated nasal septum due to congenital developmental abnormalities, while a small number of people have it due to trauma or long-term open-mouth breathing. On examination, the septum can be found to be “S”, “C” or irregularly deviated to one side. As the nasal cavity becomes narrow, it is difficult for air to enter the respiratory tract smoothly and the patient will experience unilateral nasal congestion, severe headaches and recurrent nasal bleeding, which usually requires surgery.
The second is benign or malignant tumours of the nasal cavity. The common malignant tumours are squamous cell carcinoma and melanoma. Therefore, it is important to pay attention to the sudden onset of unilateral nasal congestion and the persistent worsening of symptoms.”