ACTIONS AND USES 453 



the seed. The seed kernel contains 50 to 60 per cent, of 

 fixed oil. 



The oil is viscid, of a brownish-yellow colour, with a 

 peculiar nauseous odour and a persistent acrid taste. This 

 acridity is due to the presence of a variable small amount 

 of free crotonoleic acid. It is freely soluble in ether, chloro- 

 form, light petroleum spirit, and oils, fixed and volatile. 

 Specific gravity, 0'940 to 0'960. When the oil comes into 

 contact with the alkaline intestinal secretions and the bile, 

 it is saponified, producing glycerin and free crotonoleic 

 acid. The residual cake left after expression of the oil, 

 owing to the variable amount of oil it contains, is dangerous, 

 and should not be used. Croton tiglium seeds contain a 

 toxalbumin, Crotin, which is similar to but less toxic than 

 ricin (p. 449). Crotin is not found in the oil. 



ACTIONS AND USES. Croton oil containing free croton- 

 oleic acid irritates the living textures with which it comes 

 into contact. The oil, undiluted, and in various degrees 

 of dilution, is occasionally used as a counter-irritant, and 

 when rubbed into the skin produces an eruption which 

 becomes pustular. It is a drastic, hydragogue cathartic. 

 Full doses cause gastro-enteritis and much prostration. 

 If the free acid be removed the irritant effects on the skin, 

 mouth, and stomach, are prevented, although the purgative 

 action remains. 



GENERAL ACTIONS. Croton oil, undiluted and freely used, 

 produces pustules, seriously and deeply inflames the skin, 

 leaving permanent blemishing, and causing besides pyrexia, 

 sometimes purgation. It resembles tartar emetic in its 

 action on the skin. Used with an alkali, the irritant action 

 is more readily developed, and its effects intensified. 



Purgation is produced when the oil is freely applied to 

 the skin, or enters the body by any other channel. When 

 full doses are given, the drug is excreted not only by the 

 bowels, but by the kidneys, inducing diuresis, with much 

 irritation. As a drastic and hydragogue cathartic, croton 

 resembles gamboge and elaterium. It operates more 

 speedily than aloes, and produces more frequent, full, and 

 fluid dejections. For horses, croton is, however, too violent 

 for general use. For cattle it is sometimes valuable, 



