Allergies

Allergies – Treatment Overview

Introduction
Allergies are hypersensitivity reactions of the immune system to normally harmless substances such as foods, medications, insect venom, dust, pollen, or animal dander. They may manifest as skin conditions (urticaria, eczema), respiratory symptoms (allergic rhinitis, asthma), gastrointestinal upset, or systemic life-threatening reactions (anaphylaxis). Management depends on the severity and type of allergy, with the goals of reducing symptoms, preventing recurrence, and avoiding complications.

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Treatment Options and Doses

1. Allergen Avoidance

• Identify and avoid the triggering allergen whenever possible.

• Environmental control measures (air filters, dust-proof bedding, dietary restrictions if food allergy is confirmed).

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2. Antihistamines (first-line for mild to moderate symptoms)

• Cetirizine: 10 mg orally once daily.

• Loratadine: 10 mg orally once daily.

• Fexofenadine: 120–180 mg orally once daily.

• Children (2–6 years): Cetirizine 5 mg once daily.

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3. Corticosteroids

• Topical (for skin or nasal symptoms):

  • Hydrocortisone 1% cream: Apply 1–2 times daily to affected skin.

  • Fluticasone nasal spray: 1–2 sprays per nostril once daily (max 200 mcg/day).

• Systemic (short course for severe reactions):

  • Prednisolone: 0.5–1 mg/kg/day orally for 3–5 days, then taper.

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4. Decongestants (for nasal congestion in allergic rhinitis)

• Pseudoephedrine: 60 mg orally every 6 hours (max 240 mg/day).

• Oxymetazoline nasal spray: 1–2 sprays per nostril every 12 hours (limit ≤3 days).

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5. Leukotriene Receptor Antagonists (especially if asthma coexists)

• Montelukast: 10 mg orally once daily (5 mg chewable tablet for children 6–14 years).

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6. Management of Severe Allergic Reactions (Anaphylaxis)

• Epinephrine (first-line, life-saving):

  • Adults: 0.3–0.5 mg IM into the mid-thigh.

  • Children: 0.01 mg/kg IM (maximum 0.3 mg per dose).

  • May repeat every 5–15 minutes if needed.

• Adjunctive therapy: Oxygen, IV fluids, H1 + H2 antihistamines, corticosteroids (e.g., methylprednisolone 1–2 mg/kg IV).

• Prescribe epinephrine auto-injector (e.g., EpiPen) for patients at risk of recurrence.

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7. Long-Term and Preventive Strategies

• Immunotherapy (desensitization): Subcutaneous or sublingual for selected patients with severe allergic rhinitis, insect sting allergy, or persistent symptoms unresponsive to medication.

• Patient education: Recognizing early symptoms, carrying epinephrine auto-injector if indicated, adherence to avoidance strategies.