Immunoglobulin E (IgE) is a type of
antibody
An antibody is blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances which the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood whereas allergy, also known as allergic diseases, are a number of conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. Allergen is a substance that causes an allergic reaction. Dust, pollen and pet dander are all common allergens. Antihistamines are drugs that inhibit the physiological effects of histamine, used especially in the treatment of allergies.