Causes of a Swollen Nose
A swollen nose results from nasal mucosal inflammation, which can be triggered by infectious, allergic, non-allergic inflammatory, traumatic, or structural causes—each requiring identification of the specific etiology to guide appropriate management.
Infectious Causes
Viral Upper Respiratory Infections are the most common cause of acute nasal swelling, presenting with nasal congestion, rhinorrhea, sneezing, sore throat, and facial pressure that typically resolve within 7-14 days 1, 2. Fever, when present, occurs early (first 24-48 hours) and peaks at days 3-5 2. Common viral pathogens include rhinovirus, parainfluenza, influenza, and adenovirus 2.
Acute Bacterial Rhinosinusitis should be suspected when symptoms persist ≥10 days without improvement, severe symptoms occur (fever >39°C with purulent discharge and facial pain for ≥3 consecutive days), or "double sickening" develops (worsening after initial improvement) 3, 1. The most common bacterial pathogens are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis 1.
Chronic infections including tuberculosis, syphilis, fungal infections (sporotrichosis, blastomycosis, histoplasmosis), and rhinoscleroma (Klebsiella rhinoscleromatis) can cause persistent nasal swelling with ulceration and crusting 4.
Allergic Rhinitis
IgE-mediated allergic rhinitis causes nasal swelling through allergen binding to specific IgE antibodies on mast cells, triggering histamine release and eosinophil-dominated inflammation 5, 1. Seasonal allergens (pollens) typically cause more sneezing and rhinorrhea, while perennial allergens (dust mites, molds, animal dander) cause more obstruction 5. Key distinguishing features include nasal itching, ocular symptoms, family history of atopy, and symptom correlation with specific allergen exposures 5, 1.
Non-Allergic, Non-Infectious Rhinitis
Vasomotor rhinitis presents as nasal congestion and rhinorrhea triggered by temperature changes, humidity, odors (perfume, bleach, solvents), tobacco smoke, or irritants, without evidence of infection or allergy 1. This represents autonomic dysfunction with heightened sensitivity of nociceptive neurons to innocuous stimuli 1.
Rhinitis medicamentosa develops paradoxically from prolonged use of topical α-agonist decongestants (oxymetazoline), causing rebound nasal edema and congestion that can only be terminated by cessation of the vasoconstrictor 1.
Gustatory rhinitis causes watery rhinorrhea immediately after eating hot or spicy foods through vagally-mediated mechanisms 1.
Structural and Inflammatory Causes
Nasal polyps occur in 2-4% of the general population, typically after age 40, presenting as persistent nasal obstruction with rhinorrhea (39%), congestion (31%), and anosmia (29%) 1. They are associated with chronic rhinosinusitis, asthma (7-15% of adults), cystic fibrosis (50% of children), and aspirin-exacerbated respiratory disease (13% of nasal polyposis patients) 1. Polyps show eosinophil-dominated inflammation in non-CF adults versus neutrophil-dominated inflammation in CF patients 1.
Allergic fungal sinusitis should be considered in atopic patients with chronic sinusitis refractory to antibiotics, presenting with thick allergic fungal mucin containing eosinophils and fungal elements, nasal crusting, and polyposis 1. Total IgE is commonly elevated with positive skin testing to dematiaceous fungi 1.
Anatomic abnormalities including deviated nasal septum, enlarged turbinates, or dysfunctional nasal valve can cause primary nasal swelling and obstruction 1.
Systemic and Granulomatous Diseases
Granulomatous diseases including granulomatosis with polyangiitis (Wegener's), sarcoidosis, relapsing polychondritis, and midline granuloma present with ulcerative nasal lesions, crusting, and swelling that often precede systemic symptoms 4. These require tissue biopsy for diagnosis 4.
Atrophic rhinitis (primary or secondary) causes paradoxical nasal congestion despite mucosal atrophy, with crusting and foul odor, potentially caused by Klebsiella ozaenae, Staphylococcus aureus, or secondary to chronic granulomatous disorders, excessive turbinate surgery, trauma, or irradiation 1.
Malignancy
Nasal tumors (benign or malignant) typically cause unilateral obstruction, with rapidly growing malignancies presenting early with bleeding, hyposmia/anosmia, pain, and otalgia 4. Occupational exposure to nickel and chrome increases risk 4.
Pathophysiologic Mechanism
The common pathway for nasal swelling involves mucosal inflammation manifesting as venous engorgement, increased nasal secretions, and tissue edema, mediated by histamine, tumor necrosis factor-alpha, interleukins, and cell adhesion molecules 6. Inflammation-induced changes in sensory afferents contribute to altered perception of congestion 6.
Critical Diagnostic Pitfalls to Avoid
Do not diagnose bacterial rhinosinusitis based on purulent discharge alone—colored mucus reflects neutrophil presence, not bacterial infection, and occurs in both viral and bacterial infections 3. Bacterial diagnosis requires specific temporal patterns (persistent ≥10 days, severe symptoms, or double sickening) 3.
Do not prescribe antibiotics for viral rhinitis—40-60% resolve spontaneously, and inappropriate antibiotics drive resistance and increase candidiasis risk 3, 2.
Never assume persistent nasal ulceration or unilateral swelling is benign without biopsy—malignancy and serious systemic diseases require tissue diagnosis 4.
Recognize warning signs requiring immediate evaluation: periorbital edema, diplopia, severe headache, or visual changes suggesting orbital or intracranial complications 3.
Do not perform routine imaging for uncomplicated acute rhinosinusitis—plain films and CT have high false positive/negative rates and are unnecessary 1, 3. CT is indicated only for chronic rhinosinusitis (symptoms ≥12 weeks), treatment failures, or suspected complications 1, 7.