5.1 Allergy

Concept of Allergy

  • Definition: Exaggerated or abnormal immune response by the body to a substance (allergen) that is normally harmless to most people.
  • Immune system mistakenly identifies allergen as a threat, produces antibodies.

Allergens

  • Substances that trigger allergic reactions.
  • Common Examples: Dust, Pollen Grain, Mites, Strong Sunlight, Particular Food Items (peanuts, milk, eggs, etc.).

Entry Routes of Allergens

  • Mouth: Ingestion of allergic food items.
  • Nose: Inhalation of airborne allergens (pollen, dust, pet dander).
  • Skin: Direct contact (plants, chemicals, insect stings).

Symptoms of Allergic Reaction

  • Respiratory: Sneezing, runny nose, congestion, itchy nose, watery eyes, coughing, wheezing, shortness of breath.
  • Skin: Rashes, hives (urticaria), itching, eczema.
  • Digestive: Nausea, vomiting, diarrhea, abdominal pain.
  • Systemic (severe cases): Swelling (angioedema), difficulty breathing, low blood pressure, dizziness, loss of consciousness (anaphylaxis).

Types of Allergies

  • Seasonal Allergies (e.g., Hay Fever): Occur during specific times of year, triggered by airborne pollen.
  • Perennial Allergies: Occur year-round, triggered by indoor allergens (dust mites, pet dander, mold).

Precautions and Care

  • Identify and Avoid Allergens: Most crucial step.
  • Medication: Antihistamines, decongestants, nasal sprays.
  • Environmental Control: Keep homes clean, use allergen-proof covers, air purifiers, avoid pets if allergic.
  • Dietary Management: For food allergies, read labels, avoid trigger foods.
  • Immunotherapy (Allergy Shots): Desensitize immune system (for severe cases).
  • Carry Emergency Medication: Epinephrine auto-injector (EpiPen) for severe allergies.
  • Medical Alert Bracelet: Informs others in an emergency.