PEPSIN 691 



coated twice with keratin. This method of dispensing is 

 useful 



(1) For drugs which irritate the gastric mucous membrane 

 such as anthelmintics, arsenic, creosote, salicylic acid, 

 phosphorus, and the more soluble iron salts. 



(2) For such substances as impair digestion in the 

 stomach by precipitating pepsin and peptones e.g., tannic 

 acid, alum, lead acetate, silver nitrate, corrosive sublimate, 

 etc. 



(3) For such substances as are rendered inert by the 

 gastric juice, or are undesirably acted upon by it e.g., 

 alkalies, soaps, bile, silver nitrate, iodides, intestinal anti- 

 septics, etc. 



(4) For medicines which it is desired to introduce into 

 the bowel in as concentrated a form as possible e.g., 

 kousso, male fern extract, santonin, bile, alkalies, and silver 

 nitrate, lead acetate, or tannin, when their local action is 

 sought to be applied in ulceration or haemorrhage of the 

 intestines (Brunton). 



On pills and boluses for monogastric animals, a coating 

 of fresh mutton fat will be found more convenient than 

 keratin solution, and quite as serviceable. 



PEPSIN 



PEPSINUM. An enzyme obtained from the mucous lining 

 of the fresh and healthy stomach of the pig, sheep, 

 or calf. It should dissolve 2500 times its weight of 

 hard-boiled white of eggs (B.P.). 



Pepsin is prepared by several processes. The stomach is 

 digested in water acidulated with hydrochloric acid, and the 

 pepsin thus extracted is precipitated by sodium chloride. 

 More commonly the mucous surface is cleansed, slightly 

 washed, the surface scraped with a blunt knife, and the 

 viscid pulp thus obtained dried at a temperature not ex- 

 ceeding 100 Fahr. Pepsin occurs as a light yellowish 

 brown or white powder or in grains or scales, having a 

 faint odour and a saline taste. Soluble in water and in 

 100 parts of rectified spirit. 



