IRON 4.03 



globin is being constantly destroyed and eliminated as the coloring 

 matter of the urine and feces, more iron must be absorbed to replace 

 that which is cast off. Under normal conditions animals take a suffi- 

 cient amount with the food to satisfy this want. 



Local Action. The local action of iron is similar to that of the 

 other metals. The insoluble preparations have no effect upon the 

 unbroken skin or upon the digestive tract, unless they are converted 

 into soluble form by the secretions. Ferrous salts form soluble com- 

 pounds with the proteids which are neither irritating nor corrosive, 

 while the ferric salts precipitate the proteids in an insoluble form 

 and are therefore irritant and astringent. The soluble salts are an- 

 tiseptic and disinfectant on account of their action upon proteids. 



Internally. Iron is an astringent and may cause constipation. 

 It forms loose compounds with the proteids of the digestive tract. It 

 may be absorbed from different parts of the digestive tract, but 

 chiefly from the duodenum. According to some authors, a portion 

 of the iron is converted into the chloride by the hydrochloric acid 

 of the gastric juice, in which form it combines with the proteids. 

 Upon reaching the duodenum it is decomposed by the alkali into the 

 carbonate. 



Absorption. Dixon says, "Whether the iron is present in a 

 soluble or insoluble form, absorption of iron granules takes place 

 through the epithelial cells. These granules are taken up by the 

 leucocytes of the mucosa, and ultimately are carried into the portal 

 vein, although some find their way into the mesenteric lymph 

 glands." As in case of most other metals, iron is more rapidly ab- 

 sorbed than eliminated. The excess is deposited in the liver, spleen 

 and bone marrow until used or excreted. In the liver, iron exists as 

 easily decomposed granules (ferratin). 



Excretion. Iron is mainly excreted by the bowels, but a small 

 amount escapes in the urine. An excess of iron in the feces stains 

 them black on account of the formation of sulphides or tannates due 

 to the presence of hydrogen sulphide and ingesta with which it comes 

 in contact. 



Hemoglobin. Under normal conditions enough iron is taken in 

 the body with the food to supply what is needed and in such cases its 

 administration will have no effect upon the hemoglobin or number of 

 red cells. But, in anemias, iron will increase both the per cent, of 

 hemoglobin and the number of red cells. There is no direct evidence 

 to show whether iron supplies the necessary material for these 

 processes, promotes absorption of iron or simply stimulates the blood- 

 forming organs. 



Summary of Action. 



1. Locally iron is astringent, styptic and caustic. 



2. Internally, a. Iron stimulates hemoglobin formation and 



