DISEASES OF METABOLISM 135 



(b) The medicinal plastics correspond essentially to the foods 

 in composition and consequently consist of albumin, fat, carbo- 

 hydrates and salts. The most important are meat extract, cod 

 liver oil, sugar, starch flour, milk sugar, peptone, iron salts, cal- 

 cium salts, phosphorus, phosphates, sulphur, potassium salts, 

 sodium chloride and other salts. A former special subdivision of 

 the medicinal plastics was the peptic plastics, which included 

 pepsin and hydrochloric acid. These are referred to under physi- 

 ological stomachics (page 29). Arsenic is an indirect plastic. 



Uses. — The plastics are employed to improve nutrition in all 

 acute or chronic diseases which are accompanied by emaciation or 

 tissue reduction and especially by anaemia. These changes are 

 most frequently observed in chronic constitutional diseases, par- 

 ticularly anaemia, pernicious anaemia, leukaemia, rachitis, osteo- 

 malacia and diabetes mellitus. They also occur in many chronic 

 debilitating diseases, e.g., tuberculosis, worm cachexia, chronic 

 gastric and intestinal catarrh and carcinomatosis. Considerable 

 emaciation takes place in all acute febrile diseases in which metab- 

 olism is greatly increased, especially in the acute infectious dis- 

 eases (contagious pneumonia, canine distemper, aphthous fever). 



Plastics are contraindicated in obesity, which on the contrary 

 is to be combated with antiplastics. (See the section on anti- 

 plastics, p. 138.) 



Drugs. — 1 . *Meat extract. A valuable blood plastic in anaemia 

 and leukaemia in consequence of its content of blood salts (potas- 

 sium phosphate, iron) ; also a general plastic in chronic disturbance 

 of nutrition in carnivora. It has no particular nutritive value 

 because it does not contain albumin, carbohydrates or fats. Dose 

 for dogs, 2-10, grs. xxx to 5ijss. 



2. Oleum morrhuae. Cod liver oil. On account of its content 

 of free fatty acids and easily digested fat, an important plastic in 

 rachitis and anaemia and following exhausting diseases. Doses 

 for horses and cattle, 100-500, Siij to Oi; sheep, goats and swine, 

 50-100, 5 iss to iij ; dogs, 10-50, 5 ijss to 5 iss; fowl, 2-5, tqjxxx to 3i. 



3. *Peptone. A substitute for albumin; plastic in chronic dis- 

 turbances of nutrition in carnivora. Dose for dogs, 10-25, 3 ijss 



