DRUGS ACTING ON THE DIGESTIVE ORGANS 27 



the spleen), and lecithin and cholesterin (the waste pro- 

 ducts of nerve tissue and cellular activity). The bile pigment 

 and acids are rendered inert in the bowel by precipitation 

 in the acid chyme. 



4. Secretory Action. — Bile, as a secretion, is utilized in 

 the intestines, where it is instrumental in the emulsification 

 and absorption of food-fat and as an intestinal antiseptic. 

 Experiments on fasting, curarized dogs — from which all the 

 bile was removed through glass tubes connected with the 

 common bile duct — have shown that the following drugs 

 particularly stimulate biliary secretion. 



DIRECT CHOLAGOGUES. 



^Podophyllum Ipecac 



Aloes Euonymus 



^Rhubarb *Nitro-hydrochlorlc Acid 

 Colchicum Corrosive Sublimate 



Sodium Sulphate Sodium Salicylate 



*Sodium Phosphate 



These experiments may not apply to all animals owing 

 to the differences in food requirements and anatomy. The 

 drugs marked with an asterisk have been found by clinical 

 evidence most valuable. The purgatives above-mentioned 

 act most successfully as cholagogues when given in small 

 doses. 



INDIRECT CHOLAGOGUES. 



Calomel 

 Mercury 

 Most purgatives in a less degree. 



The bile occurring at any tipae within the bowels is in 

 part absorbed and then re- secreted. This process may be 

 repeated indefinitely, but is prevented by purgatives, espe- 

 cially those increasing peristalsis in the duodenum and 

 upper part of the jejunum (calomel), because they hurry 

 along and expel the bile in the gut before it has time to be 

 absorbed. 



In this way calomel and purgatives are indirect chola- 

 gogues in removing bile from the body ; not by stimulating 

 its secretion, but by hastening its excretion from the bowels. 



