Definition
Hay fever, medically known as allergic rhinitis, is an IgE-mediated inflammatory condition of the nasal mucosa caused by exposure to airborne allergens. It is characterized by nasal congestion, rhinorrhea, sneezing, and itching, often accompanied by ocular symptoms.
Etiology and Triggers
Common allergens:
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Seasonal (pollen from trees, grasses, weeds) – seasonal allergic rhinitis
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Year-round (dust mites, pet dander, molds) – perennial allergic rhinitis
Pathophysiology:
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Upon exposure, allergens cross-link IgE bound to mast cells in nasal mucosa → release of histamine, leukotrienes, prostaglandins
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This triggers vasodilation, increased vascular permeability, mucus secretion, and stimulation of sensory nerves → classic symptoms
Risk Factors
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Family history of atopy (asthma, eczema, allergic rhinitis)
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Coexisting allergic conditions
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Early life exposure to allergens and environmental factors
Clinical Features
Nasal symptoms
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Sneezing (often in bouts)
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Watery rhinorrhea
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Nasal congestion and obstruction
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Nasal itching
Ocular symptoms
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Itchy, watery, red eyes
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Periorbital swelling
Other
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Itchy throat, palate, or ears
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Postnasal drip, cough (from mucus)
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Fatigue, sleep disturbance in severe cases
Examination findings
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Pale, boggy nasal mucosa
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Clear nasal discharge
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Allergic shiners (dark circles under eyes)
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Dennie–Morgan folds (infraorbital skin folds)
Diagnosis
Primarily clinical based on history and examination.
Further testing indicated in uncertain or severe cases:
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Skin prick testing to identify specific allergens
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Serum specific IgE testing
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Nasal smear (eosinophil count) in selected cases
Management
Goals: Reduce symptoms, improve quality of life, and minimize exposure to allergens.
1. Allergen Avoidance
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Keep windows closed during high pollen seasons
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Use air conditioning and HEPA filters indoors
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Shower and change clothes after outdoor exposure
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Wash bedding in hot water weekly to reduce dust mites
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Limit outdoor activity in early morning and windy days during pollen season
2. Pharmacological Treatment
A. Oral non-sedating antihistamines – First-line for mild to moderate symptoms
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Cetirizine: Adults 10 mg once daily; children dose per weight
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Loratadine: Adults 10 mg once daily; children dose per weight
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Fexofenadine: Adults 120–180 mg once daily; children dose per weight
B. Intranasal corticosteroids – Most effective for moderate to severe symptoms; reduce nasal inflammation
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Fluticasone propionate: 50 mcg per spray; 1–2 sprays per nostril once daily
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Mometasone furoate: 50 mcg per spray; 1–2 sprays per nostril once daily
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Budesonide: 64 mcg per spray; 1 spray per nostril twice daily
C. Intranasal antihistamines – Rapid relief, can be combined with corticosteroids
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Azelastine: 1 spray per nostril twice daily
D. Oral or intranasal decongestants – Short-term relief of nasal congestion (max 3–5 days for intranasal use to avoid rebound congestion)
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Pseudoephedrine: 60 mg orally every 4–6 hours (adults)
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Oxymetazoline nasal spray: 0.05%, 1–2 sprays per nostril twice daily (max 3 days)
E. Ocular symptoms – Antihistamine eye drops
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Olopatadine 0.1%: 1 drop in each eye twice daily
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Ketotifen 0.025%: 1 drop in each eye twice daily
3. Immunotherapy
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Subcutaneous immunotherapy (SCIT) or sublingual immunotherapy (SLIT) for patients with severe symptoms despite optimal medical therapy or for those wishing to reduce long-term medication use
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Administered under specialist supervision over 3–5 years
Special Considerations
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In children, prefer non-sedating antihistamines to avoid school performance impairment
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In pregnant women, loratadine and cetirizine are generally considered safe; intranasal corticosteroids such as budesonide have good safety profiles
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Comorbid asthma should be assessed and treated concurrently
Prognosis
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Symptoms may fluctuate with seasons or allergen exposure
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Good control achievable with allergen avoidance and medication
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Immunotherapy may provide long-term remission
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