238 CATHARTICS AND PURGES. 



CATHARTICS and PURGES. 

 Purgative Oils. 



Castor Oil is decomposed in the small intestine, and the resulting ricinolates are 

 so irritant as to induce increased secretion and peristalsis. 



Castor oil is used as a broom to sweep putrefactive masses out of the intestines. 



Dose. Oleum Ricini, 4 to 30 mils. 



Croton Oil is similarly decomposed in the small intestine into glycerin and cro- 

 tonoleic acid and a resinous anhydride which latter is very irritant 



Croton oil is used in emergencies, or as a drastic purge to relieve cerebral con- 

 gestion. 



Dose. Oleum Tiglii, 0.02 to 0.05 mil. 



. 

 Anthracene Purgatives. 



Rhubarb probably irritates the mucosa of the jejunum and ileum. It is useful in 

 fermentative diarrheas. 



Dose. Tinctura Rhei Aromatica, 2 mils. 



Senna mildly stimulates the whole small intestine. It is useful as a simple cathar- 

 tic for children. 



Dose. Tinctura Sennse Composita, 8 to 15 mils. 



Aloes is said to stimulate the mucosa of the sigmoid and rectum. It is useful as 

 a temporary measure in depressed peristalsis of the lower bowel. 



Dose. Aloes, 0.25 Gm. 



Cascara is said to increase secretion into the rectum. It is the one safe drug to 

 use in chronic constipation of the simple type characterized by hard infrequent stools. 



Dose. Fluidextractum Cascarse Sagradae Aromaticum, i mil, much diluted with 

 water. 



Resinous Glucosides. 



These act by irritating the mucosa, sometimes producing inflammatory exudates. 

 The seat of action is chiefly the small intestine, and the presence of bile seems essential. 



The resinous glucosides are used to clear out the bowel, especially in those en- 

 cumbered conditions due to overeating. 



Dosage. Resina Podophylli, 0.005 to -3 Gm. ; Resina Jalapae, o.i to 0.3 Gm. 



Salines. 



The saline cathartics act by increasing the fluidity of the intestinal contents 

 thereby stimulating peristalsis. This increased fluidity is due to a retardation of ab- 

 sorption produced by the salines and to an exosmosis caused by the hypertonicity of 

 the salts. 



Salines are useful whenever a quickly-acting, non-irritating flushing out of the 

 bowels seems desirable. 



Dosage. Magnesii Sulphas, 2 to 30 Gm. ; Sodii Phosphas, 2 to 30 Gm. ; Pulvis 

 Effervescens Compositus, i powder. 



