Local anaesthesia through the action of cocaine, the oral mucosa and the Vienna group.

Local anaesthesia through the action of cocaine was introduced in Europe by the Vienna group, which includeed Freud, Koller and Königstein. Before using the alkaloid in animal or human experimentation all these scientists tested it on their oral mucosa - so-called self-experimentation. Some of them with different pathologies (that is, in the case of Freud), eventually became addicted to the alkaloid. Here we attempt to describe the people forming the so-called 'Vienna group', their social milieu, their experiences and internal disputes within the setting of a revolutionary discovery of the times.