Title: hypersensitivity
Long Title: IUPAC Gold Book - hypersensitivity
DOI: 10.1351/goldbook.13241
Status: current

Definition
State in which an individual reacts with allergic effects following exposure to a certain substance (allergen) after having been exposed previously to the same substance. It is sometimes used loosely for any increased response.

Note
Four types of hypersensitivity are recognized. Most common chemically induced allergies are type I [immunoglobulin E- (IgE-) mediated] and type IV (cell-mediated) hypersensitivity.

Related Terms
- Gell and Coombs classification: https://goldbook.iupac.org//terms/view/13167
- allergen: https://goldbook.iupac.org//terms/view/12857
- allergic: https://goldbook.iupac.org//terms/view/12858
- allergy: https://goldbook.iupac.org//terms/view/12859
- immunoglobulin E- (IgE-): https://goldbook.iupac.org//terms/view/13288

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1180 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13241/html
- json: https://goldbook.iupac.org/terms/view/13241/json
- xml: https://goldbook.iupac.org/terms/view/13241/xml

Citation: Citation: 'hypersensitivity' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.13241
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Accessed: 2026-04-18T00:19:18+00:00