Digestive Health Irritable Bowel Syndrome Atopy and Atopic Disease By Barbara Bolen, PhD Updated on February 03, 2020 Medically reviewed by Priyanka Chugh, MD Print Atopic is a term used to describe an IgE-mediated response within the body following exposure to external irritants. Martin Leigh/Getty Images The Difference Between Atopy and Allergy Most of us are acquainted with the term "allergy." We understand that it is an exaggerated body reaction to an external irritant. Allergies cover a broad range of reactions. Atopy, on the other hand, refers to a genetic predisposition to diseases in which IgE antibodies are produced in response to even limited exposure to environmental triggers that don't typically bother other people. Thus, all atopic reactions are allergies, but not all allergies involve atopic responses. Often the two words are used interchangeably, although in clinical practice doctors are much more likely to use the word allergy. Atopic Diseases The following list contains the most common types of atopic disease: Allergic asthma Atopic dermatitis, also known as atopic eczema Allergic rhinitis (hay fever) What Causes an Atopic Reaction? When a person who has an atopic disease is exposed to an allergen, an IgE response occurs that causes immune and blood cells to release substances, such as histamines, that trigger a variety of physical changes within the body. These changes can affect blood vessels, stimulate secretion of mucus, affect muscle functioning and create inflammation within cells of certain parts of the body. With atopy, genetic factors are typically involved, although environmental factors appear to play a role in both onset and maintenance of symptoms. Common Triggers As you will see, many of the triggers for atopy are air-borne: Animal dander Dust Dust mite droppings Mold Pollen Symptoms may also be triggered by contact with certain chemicals, certain types of fabrics, and other environmental irritants. Symptoms As you will see, many of the symptoms of atopy are those that you would associate with an allergic reaction: Hives, welts, scaling or other signs of skin irritationItching of the eyes, nose or skinNasal congestionRedness of the eyesA runny noseSinus pain and/or swellingSneezing The following symptoms indicate anaphylaxis which can be life-threatening and thus require immediate medical attention: Wheezing, shortness of breath or any difficulty breathingRapid or slowed heartbeatAny signs of mental confusion or loss of consciousness 5 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. American Academy of Allergy, Asthma and Immunology. Atopy Definition. UpToDate. The relationship between IgE and allergic disease. Moreno MA. JAMA Pediatrics Patient Page. Atopic Diseases in Children. JAMA Pediatr. 2016;170(1):96. doi:10.1001/jamapediatrics.2015.3886 Caubet JC, Eigenmann PA. Allergic triggers in atopic dermatitis. Immunol Allergy Clin North Am. 2010;30(3):289-307. doi:10.1016/j.iac.2010.06.002 Merck Manuals. Anaphylactic Reactions. July 2019. Additional Reading Lillestøl K, Helgeland L, Arslan lied G, et al. Indications of 'atopic bowel' in patients with self-reported food hypersensitivity. Aliment Pharmacol Ther. 2010;31(10):1112-22. doi:10.1111/j.1365-2036.2010.04261.x By Barbara Bolen, PhD Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit