Understanding Winter Allergies: Indoor Triggers and Management

Winter allergies are driven by indoor allergens and irritants, often overlooked because seasonal pollen is low.

Key Indoor Allergens

• Dust mites: Thrive in humidity >50%; bedding, upholstery, carpet. Allergen = fecal pellets.
• Pet dander: Cat (Fel d 1), dog (Can f 1) proteins in saliva/skin; airborne for months.
• Mold: Damp areas (basement, bath, kitchen); Alternaria, Cladosporium, Aspergillus.
• Cockroach: Urban housing; potent sensitizer.

Aggravating Factors

• Forced-air heating: Circulates allergens; dries mucosa → hyperreactivity.
• Cold, dry air: Direct bronchial irritation; mimics/allergy exacerbation.
• Viral infections: Rhinovirus, RSV, flu → symptom overlap; post-viral bronchial hyperresponsiveness.
• Holiday triggers: Live trees (mold, pollen), stored decorations (dust), scented candles (VOCs).

Diagnosis and Management

• Allergy testing (skin prick or serum IgE) identifies sensitivities.
• Environmental control: allergen-proof bedding, HEPA vacuum, humidity 30–50%, pet restriction, mold remediation.
• Medications: intranasal corticosteroids (first-line), antihistamines, leukotriene modifiers.
• Immunotherapy (SCIT/SLIT) for long-term modification.

Winter "colds" that persist >2 weeks or recur annually suggest allergy. See an allergist for targeted therapy.