Chronic nasal obstruction is a frequent symptom of seasonal allergic rhinitis and perennial (year-round) allergic rhinitis. This allergic condition may have a debilitating effect on the nasal turbinates, the small, shelf-like, bony structures covered by mucous membranes (mucosa).

The turbinates protrude into the nasal airway and help to warm, humidify, and cleanse air before it reaches the lungs. When exposed to allergens, the mucosa can become inflamed. The blood vessels inside the membrane swell and expand, causing the turbinates to become enlarged and obstruct the flow of air through the nose. This inflammation, or rhinitis, can cause chronic nasal obstruction that affects individuals during the day and night.

Enlarged turbinates and nasal congestion can also contribute to headaches and sleep disorders such as snoring and obstructive sleep apnea, because the nasal airway is the normal breathing route during sleep. Once turbinate enlargement becomes chronic, it is irreversible except with surgical intervention.