The term anaphylaxis was coined by Charles Richet and Paul Portier when they tried to immunize dogs with actinia extracts, but after a repeated injection of a small amount of the toxin the dog died within 25 min. The new term rapidly spread all over the world. The discovery of the phenomenon of anaphylaxis showed that by immunization not only protection but also harmful events could be induced. For this discovery Richet received the Nobel Prize in 1913, but he still believed the condition of anaphylaxis was a lack of protection to the poisonous effect of the substance. Already earlier similar clinical phenomena had been observed but not well described. A major breakthrough in understanding the pathophysiology came through the experiments of Dale and Laidlaw who showed that the newly discovered histamine was able to induce quite similar symptoms to anaphylaxis. For decades reactions mimicking anaphylaxis but without involvement of the immune systems were called 'anaphylactoid', 'allergy-like' or 'pseudo-allergic'. Since the new definition of the World Allergy Organization (WAO) anaphylaxis is defined on the basis of clinical symptoms independent of pathomechanisms involved: one distinguishes between allergic and non-immune anaphylaxis. Epinephrine (Adrenalin) was soon recognized as treatment of choice of this dramatic condition.