Allergy

An allergy is an overreaction of the body's immune system to a harmless substance, such as:

1. Foods (e.g., peanuts, gluten)

2. Pollen

3. Dust mites

4. Insect stings

5. Medications

6. Latex

When an allergic person encounters an allergen, their immune system mistakenly identifies it as harmful and triggers a response to fight it off.

Key characteristics:

1. Hyperensitivity: Exaggerated response to a stimulus.

2. Immunological: Involves the immune system.

3. Specific: Reaction to a specific substance.

Types of allergies:

1. IgE-mediated: Immediate reaction (e.g., anaphylaxis).

2. Non-IgE-mediated: Delayed reaction (e.g., celiac disease).

3. Food intolerance: Non-immune system reaction (e.g., lactose intolerance).

Symptoms:

Varies depending on the allergy and individual:

- Skin: hives, itching, swelling

- Respiratory: congestion, coughing, wheezing

- Gastrointestinal: nausea, vomiting, diarrhea

- Cardiovascular: rapid heartbeat, fall in blood pressure

- Anaphylaxis (life-threatening): constricted airways, loss of consciousness

Treatment:

1. Avoid exposure to allergens

2. Medications (antihistamines, corticosteroids)

3. Immunotherapy (desensitization)

4. Emergency treatment (epinephrine auto-injectors)