OLEUM RICINI. 327 



Croton oil is used when a speedy and complete evacuation 

 of the bowels, and diminution of the arterial pressure, are 

 demanded. It is a proper purgative in some cases of apoplexy ; 

 in intestinal obstruction from impacted faeces ; or where other 

 purgatives have failed in constipation, and an organic obstacle 

 does not exist. The smallness of the dose, which can be put 

 in food, renders it a convenient purgative for insane and un- 

 conscious patients. Croton oil must always be given with 

 great care ; and is inadmissible in feeble subjects, in organic 

 obstruction, and in inflammatory states of the stomach and 

 intestines. 



2. ACTION IN THE BLOOD J SPECIFIC, AND REMOTE LOCAL 

 ACTION. 



Crotonic acid, or its products, are occasionally absorbed, 

 and cause disturbance of the heart and nervous centres. 



Oleum Ricini CASTOR OIL. The oil expressed 

 from the seeds of Bicinus communis. Imported chiefly 

 from Calcutta. 



Characters of the seeds. Oval, somewhat compressed, 

 smooth and shining, grey, marbled with reddish-brown or 

 blackish-brown spots and stripes. 



Substance resembling Castor Oil Seed : Croton Oil Seed (q.v.). 



Characters of the oil. Viscid, colourless, or pale straw 

 yellow, having a slightly nauseous odour and a somewhat acrid 

 taste. Entirely soluble in one volume of alcohol and in two 

 volumes of rectified spirit. 



Composition. The bulk of castor oil consists of ricinoleic 

 acid, CisH^Oa, combined with glycerine. Palmitin, stearin, 

 cholesterin, and possibly a resin and an alkaloid also occur in 

 small quantities. 



Dose. 1 to 8 fl.dr. 



Preparations. 



Oleum Sicini is contained in : Collodium Flexile (1 in 49), 

 Linimentum Sinapis Compositum (1 in 9), and Pilula Hy- 

 drargyri Subchloridi Composita (1 in 5). 



ACTION AND USES. 

 1. IMMEDIATE LOCAL ACTION AND USES. 



Externally, pure castor oil is bland, like almond oil ; and 

 is applied as a local sedative and protective, for instance, in 

 injury of the conjunctiva by quicklime. 



