IgE-mediated Hypersensitivity

IgE-mediated hypersensitivity is an allergic reaction where the immune system overreacts to a normally harmless substance, called an allergen (like pollen or pet dander). When exposed, the body produces a specific antibody called IgE, which triggers immune cells to release chemicals such as histamine. This release causes allergy symptoms like sneezing, runny nose, itching, or swelling. These reactions happen quickly and can range from mild to severe, sometimes causing anaphylaxis, a life-threatening emergency. This type of allergy is common and is the basis for many allergic diseases people experience.