Common Causes of Nasal Congestion in Rhinitis
The most common causes of nasal congestion in rhinitis are viral infections and allergic responses to airborne allergens, with nonallergic rhinitis representing a significant additional category that includes vasomotor, medication-induced, and postinfectious etiologies. 1, 2
Primary Etiologic Categories
Allergic Rhinitis
Allergic rhinitis is the leading identifiable cause of chronic nasal congestion, affecting approximately 15% of the US population (50 million individuals) 3. The mechanism involves:
- IgE-mediated inflammation triggered when allergens penetrate the nasal mucosal epithelium, inducing a T-helper type 2 inflammatory response 3, 4
- Nasal congestion occurs predominantly during the late-phase allergic response (4-8 hours after allergen exposure), while the early phase (within minutes) produces more sneezing, itching, and rhinorrhea 4
- In international studies, nasal congestion was reported by 94.23% of allergic rhinitis patients, making it the most prevalent symptom 3
Common allergen triggers include:
- Seasonal allergens: pollens from trees, grasses, and weeds causing seasonal allergic rhinitis (SAR) 1, 4
- Perennial allergens: house dust mites, molds, and animal dander causing year-round symptoms 1, 4
- Patients with perennial allergic rhinitis typically present with erythematous and inflamed turbinates, while seasonal allergic rhinitis shows edematous and pale turbinates on examination 3
Viral Rhinitis
- Viral infections are the most common acute cause of nasal congestion, typically lasting up to 10 days as part of the common cold syndrome 1
- This represents a self-limited inflammatory process affecting the nasal mucosa 1
Nonallergic Rhinitis
Nonallergic rhinitis accounts for a substantial proportion of chronic rhinitis cases and is divided into inflammatory and noninflammatory subtypes 2:
Inflammatory causes:
- Nonallergic rhinitis with eosinophilia syndrome (NARES) 2
- Postinfectious rhinitis (persistent inflammation following viral infection) 2
- Rhinitis associated with nasal polyps 2
Noninflammatory causes:
- Idiopathic nonallergic (vasomotor) rhinitis: characterized by nasal hyperreactivity to nonspecific triggers like temperature changes, humidity, irritants, and strong odors 1, 2
- Medication-induced rhinitis: particularly from prolonged use of topical nasal decongestants causing rebound congestion (rhinitis medicamentosa) 1
- Hormone-related rhinitis: including pregnancy-associated rhinitis 2
- Systemic disease-related rhinitis 2
Key Distinguishing Features
Allergic vs. Nonallergic Rhinitis:
- Itching and ocular symptoms are more characteristic of allergic rhinitis 1
- Nonallergic rhinitis presents primarily with nasal congestion and postnasal drainage, often with sinus pressure, ear plugging, and eustachian tube dysfunction 3
- Patients with nonallergic rhinitis have negative IgE testing for aeroallergens 3
Important Clinical Pitfalls
- Nonspecific nasal hyperreactivity occurs in both allergic and nonallergic rhinitis patients, meaning allergic patients often experience severe symptoms from irritant exposure that may exceed their response to allergens themselves 1
- In short-lived rhinitis lasting 7-10 days, differentiating between viral and allergic causes can be challenging without systemic infection signs like fever and malaise 1
- Rebound congestion from nasal decongestants can occur after just several days of use, creating a cycle where patients require decongestants even when allergens are no longer present 1