A Brief Discussion on Allergic Reactions, March 9, 1995

A Brief Discussion on Allergic Reactions, March 9, 1995

1. Type I allergic reaction

Also known as immediate-type or reaginic reaction. This type is the most common, essentially a reaginic reaction: when an allergen enters the body, immunoglobulin IgE (reagin) is immediately produced, which binds to mast cells and basophils in the blood, triggering a series of complex biological changes. The essence of these changes is the release of histamine, kinins, slow-reacting substances, and eosinophils, leading to symptoms such as urticaria, allergic rhinitis, bronchial asthma, runny nose, vomiting, abdominal pain, diarrhea, and in severe cases, shock.

2. Type II allergic reaction

Also known as cytotoxic or cell-lysing reaction. Examples of this type include neonatal jaundice and hemolytic anemia.

3. Type III allergic reaction

Also known as antigen-antibody complex reaction, such as chronic nephritis and rheumatoid arthritis.

4. Type IV allergic reaction

Also known as delayed-type allergic reaction, such as delayed reactions to drugs and rabies.