Allergy

Definition

An allergy is an exaggerated immune response to a substance that is typically harmless, known as an allergen. This response can cause symptoms ranging from mild irritation to severe reactions like anaphylaxis.

5 Must Know Facts For Your Next Test

1. Allergens can include pollen, pet dander, food, insect stings, and medications.
2. The immune system produces Immunoglobulin E (IgE) antibodies when it encounters an allergen.
3. Histamine release by mast cells during an allergic reaction leads to symptoms such as itching, swelling, and redness.
4. Common allergic conditions include hay fever, asthma, eczema, and food allergies.
5. Anaphylaxis is a severe allergic reaction that can be life-threatening and requires immediate medical attention.

Review Questions

• What types of substances commonly act as allergens?
• Which antibody is primarily involved in allergic reactions?
• What are the typical symptoms caused by the release of histamine during an allergic reaction?

Related terms

Immunoglobulin E (IgE): A type of antibody that plays a crucial role in the body's allergic response.

Histamine: A compound released by mast cells that causes many of the symptoms associated with allergies.

Anaphylaxis: A severe, potentially life-threatening allergic reaction requiring immediate medical intervention.