A fixed oil expressed from the seeds of Croton Tiglium, Linné (Nat. Ord. Euphorbiaceae). East Indies and Molucca, and Philippine Islands; cultivated in Europe and China.
Description.—A pale yellow or brown-yellow, somewhat viscid oily liquid, slightly fluorescent and having a feeble but characteristic odor. It should not be tasted, and must be handled with extreme care for it causes a papular eruption. Soluble freely in oils, ether, and chloroform, and slightly (more readily if old) in alcohol. Dose, 1 drop.
Principal Constituents.—Many (9 at least) glycerides of volatile acids, of which crotonoleic acid (C6H8O2) is the chief; fatty acids free and combined; a non-purgative but vesicant resin, crotonol (C18H28O4).
Action and Toxicology.—Croton oil is a violent irritant causing erythematous redness, intense burning pain, and an eruption of small vesicles which readily become pustular. Edematous inflammation may follow. Owing to umbilication of some of the vesicles the eruption may be mistaken for that of small-pox, but there is considerable variation in size, thus distinguishing them from that disease. Internally a single drop will quickly cause purgation. Even its external use has been followed by catharsis. An overdose produces marked gastro-intestinal inflammation accompanied by pain, griping, vomiting, and hydragogue catharsis, bloody stools, and death. Usually the vomiting prevents a fatal issue. In poisoning by it free emesis should be provoked, and opiates should be given for the pain and to restrain purgation, and demulcents to control the irritability of the mucosa. In case collapse threatens, external heat should be applied and heart stimulants be given subcutaneously.
Therapy.—External. Croton oil is now seldom used externally, and its reckless use by the profession of years ago was one of the causes that led to the opposition which resulted in the formation of the Eclectic school in medicine.
Internal. Croton oil is remarkable as a rapidly acting and certain drastic cathartic, reserved chiefly as an emergency remedy when other cathartics fail. The smallness of the dose (one to two drops in bread) and its prompt and thorough effects make it the most useful purgative for the insane and the unconscious (place a drop far back upon the tongue), and as a revulsive in cerebral congestion and apoplexy, to lower intracranial blood pressure through dilation of the vessels of the bowels. It is the most efficient purgative in lead colic with obstipation, obstinate constipation when no inflammation is present, fecal impaction without intestinal obstruction, and in comatose states as a revulsive. It may be used in puerperal eclampsia and in uremia for its derivative effects. Croton oil usually acts upon the bowels in less than an hour and occasions much borborygmus. As a rule it does not greatly debilitate the patient. It is not a good cathartic in dropsical conditions because it cannot be repeatedly administered without harm. Neither should it be used, if possible to avoid it, in children and the feeble and pregnant, nor where hemorrhoids, intestinal or renal inflammation, or peritonitis are present.