Anaphylaxis occurs when the immune system overreacts to an allergen by rapidly releasing inflammatory mediators from mast cells and basophils. This process is usually triggered by immunoglobulin E (IgE) antibodies binding to the allergen, causing these cells to release chemicals like histamine, prostaglandins, leukotrienes, and platelet-activating factor. These mediators cause symptoms such as vasodilation, increased vascular permeability, bronchoconstriction, and increased heart rate, leading to widespread allergic symptoms including skin rash, airway narrowing, low blood pressure, and shock. The reaction can happen within minutes of exposure to triggers like foods, insect stings, medications, or latex and can be life-threatening if not treated promptly.
