Immunology. An inflammatory reactions produced by an antigen combining with IgE bound to a mast cell that produces degranulation of the mast cell and subsequent release of histamine and histamine like substances. This can produce a localised or global immune reponse that results in an acute allergic reaction with shortness of breath, rash, wheezing, hypotension. See: hypersensitivity. Anaphylaxis is a serious allergic reaction that is rapid in onset and may cause death. It typically causes a number of symptoms including an itchy rash, throat swelling, and low blood pressure. Common causes include insect bites/stings, foods, and medications. On a mechanistic level, anaphylaxis is caused by the release of mediators from certain types of white blood cells triggered either by immunologic or non-immunologic mechanisms. It is diagnosed on the basis of the presenting symptoms and signs. The primary treatment is injection of epinephrine, the administration of intravenous fluids, and positioning the person flat, with other measures being complementary. Worldwide, 0.05–2%  of the population is estimated to have anaphylaxis at some point in life, and rates appear to be increasing. The term comes from the Greek words áĽ€Î˝Î¬  ana, against, and Ď†ĎŤÎ»Î±ÎľÎąĎ, phylaxis, protection. 3. An OSH glossary used in safety and health at work which is, adopted by ILO