450 ANIMAL DRUGS 



TEST. Pancreatin acts best in alkaline medium (is injured by acids). If 

 there be added to 4 fl. oz. of tepid water contained in a suitable flask 

 or bottle, first 5 gr. of pancreatin, 20 gr. of bicarbonate of sodium, 

 and afterward one pint of fresh cow's milk previously heated to 38C. 

 (ioo.4F.), and if this mixture be maintained at the same temperature 

 for thirty minutes, the milk should be so completely peptonized that, 

 upon adding to a small portion of it transferred to a test-tube a slight 

 excess of nitric acid, coagulation should not occur. This test we 

 have found quite satisfactory as a convenient one. An alternate 

 method of assay is based on the property of an aqueous solution of 

 the principle to digest (or liquefy) starch paste. The U.S. P. IX fur- 

 nishes the two tests one indicating its power in peptonizing milk, 

 the other its power in digesting starch. A limit of fat is adopted as 

 one of the standards: Two grammes of pancreatin should not yield 

 to ether more than 0.6 Gm. of fat. 



ACTION AND USES. Used as a digestive agent, especially for "peptoniz- 

 ing" milk. Dose: 10 gr. (0.6 Gm.). 



RENNINUM. Rennin, N.F. Partially purified, milk-curdling enzyme 

 from the calf's stomach, capable of coagulating not less than 12,500 

 times its weight of fresh cow's milk. For assay see N.F. 



631. ADEPS LAN,E H YD ROSUS. LANOLIN 

 HYDROUS WOOL-FAT 



The purified fat of the wool of sheep, Ovis aries Linn (Fam. Bovidae), mixed 

 with not more than 30 per cent, of water. For Tests see U.S.P. 



DESCRIPTION. A yellowish-white unctuous mass. Faint, peculiar odor. 



Insoluble in water, but miscible with twice its weight. Melts at 



about 4oC. (io4F.). Adeps Lanag, U. S., is the above freed from 



water. 

 CONSTITUENTS. Cholesterin, palmitin, olein, the first mentioned being 



largely represented. 

 USES. As an inunction and vehicle for substances the medicinal action 



of which can be obtained by local application. It is employed in 



several official ointments. 



631 a. HYDROCARBON FATS AND OILS. (Petrolatum, etc.). 



DESCRIPTION, SOURCE, ETC. As a most valuable addition to the list 

 of ointment bases and oleaginous liquids there has been officially recognized: 

 Petrolatum album (White Petrolatum); Petrolatum Liquidum (oil); Petro- 

 latum Molle (soft Petrolatum); and Petrolatum Spissum (Hard Petrolatum). 

 These are mixtures of the harder and softer members of the paraffin series 

 of hydrocarbons, having different melting and congealing points, etc. Hard 

 paraffin consists chiefly of hydrocarbons ranging from Czo^s to CaoHez; 

 soft paraffin consists chiefly of Ci&H 3 z to Czofitz', liquid consists chiefly 

 of heptane, CyHie, and octane, CgHis. 



USE. 'As a vehicle for medicinal substances applied locally. As such it is 

 much less permeable through the skin than other fats. 



