causes of nasal obstruction
Greater than 60% of rhinitis patients over the age of 50 suffer from a non-allergic aetiology. The causes of nasal obstruction are: 1  Infective rhinitis: acute rhinitis is often infective in origin. 2  Viral rhinitis is one of the most frequent causes of nasal obstruction. 3  Rhinoviruses, respiratory syncytial virus, parainfluenza and influenza viruses and adenoviruses are among the viruses most commonly identified.