“‘Principal indications: Intestinal dyspepsias, intestinal autointoxications, certain forms of constipation and duodenal insufficiency.’ “At the International Congress of Medicine, Madrid, 1903, Hallion said that he felt justified in stating that _duodenal opotherapy correctly carried out must be classed under the very best methods of treating dyspepsia_.[106] The results had been satisfactory and, in many cases, remarkable. It had been nil in a few cases but it had never been harmful in any degree. He pointed out that Marfan was the first to employ this substance clinically. Marfan had had particularly excellent results in children of 15 months to 4 years suffering with marked malnutrition, anorexia and constipation. _Marfan prescribed the duodenal extract given in milk._[106] Hallion further remarks that, as he is not a practitioner, he had had only one opportunity to test duodenal opotherapy clinically. The case was that of a man of 26 years with obstinate intestinal dyspepsia and severe constipation which had persisted from childhood. This patient had been treated by enemas, laxatives, diet, etc. _Treatment with duodenal extract resulted in a complete cure._[106] Hallion points out _that the most satisfactory aspect of duodenal opotherapy is the permanent effect produced_,[106] which bears out his statement that these extracts have the power to aid in the restoration of function and structure of an organ. “This has been so well established that the principle is now embodied in a law which is frequently referred to as ‘Hallion’s Law’: ‘Extracts of an organ exert on the same organ an exciting influence which lasts for a longer or shorter time. When the organ is insufficient it is conceivable that this influence augments its action and, when it is injured, that it favors its restoration.’ “In ‘La Pratique de l’Opothérapie’ Hallion points out that ‘the opotherapeutic product which corresponds to the affected organ represents in some way the stimulating and elective food for that organ, and if we supply the organ with a food which is more complete than it necessarily needs, the affected organ can exercise its elective action and take up only those substances of which it is in need.’ “Hallion’s observations on this point are beautifully borne out by the classic work of J. W. Draper, as reported in The Journal of the American Medical Association, Sept. 26, 1914. This report gives results in both laboratory and clinical experiments.