116 CHOLAGOGUES 



strychnine, veratrine, antipyrine, cocaine, and other alka- 

 loids, are detained and their action is delayed. This im- 

 portant power of the liver to delay the action of or actually 

 to destroy poisons, whether elaborated in the vital processes 

 or introduced from without, is illustrated in Lautenbach's 

 experiments. One-twentieth of a drop of nicotine does not 

 kill a frog, but half that dose suffices when the liver has been 

 removed. 



The bile has various functions. It promotes absorption 

 and assimilation of fats. It moistens the intestinal walls, 

 and excites contraction of their muscular coat, thus acting as 

 a natural laxative. 



DIRECT CHOLAGOGUES increase the formation of bile, and 

 are represented first and foremost by bile salts themselves, 

 put into the blood stream. Others are dilute nitro-hydro- 

 chloric acid, sodium salicylate and benzoate, turpentine, 

 podophyllum, euonymin. Some of these drugs augment the 

 quantity of bile without altering its quality ; others, like 

 sodium salicylate, increase the quantity and fluidity ; 

 others, such as toluylendiamine, increase the solid parts, 

 rendering it so viscid that it cannot readily pass through the 

 bile ducts, and hence becomes reabsorbed, and may produce 

 jaundice. Healthy dogs with biliary fistulse, liberally fed 

 with fats and oils, were found to secrete more bile than when 

 freely fed on albuminoids or carbo-hydrates. It is of little 

 practical importance to increase biliary secretion, although 

 often necessary to remove excess of bile from the intestines. 

 This can be done by the administration of purgatives. 



INDIRECT CHOLAGOGUES remove bile from the body mainly 

 by increasing intestinal action. Excess of bile is apt to lodge 

 in the small intestine, and become reabsorbed. Effectually 

 to get rid of it, the bowels must be freely moved, preferably 

 by a purge, which will produce sufficient fluid to wash out the 

 small intestine. The drugs which effect this are calomel and 

 other purgative mercurial salts, given with a cathartic, such 

 as aloes, jalap, podophyllum, or sulphates of magnesium and 

 sodium. Their effects are increased by active exertion. In 

 dogs and other animals that vomit, emetics effectually 

 remove bile by compressing the liver between the diaphragm 

 and the abdominal muscles, diluting the bile with abundant 



