168 iitoeganic agents 



Aluminum Salts. 



'Action External. — Dried alum is a superficial caustic, in 

 contact with raw surfaces, on account of its affinity for water. 

 It is only used externally. Alum has no action on unbroken 

 skin, but applied to mucous membranes or denuded parts it is 

 antiseptic and astringent; coagulates albumin of discharges; 

 precipitates or coagulates albumin of the tissues; squeezes 

 blood out of the vessels ; reduces inflammation and makes the 

 part whiter, tougher and denser. Alum is an haemostatic, 

 stopping bleeding by compression of the structures surround- 

 ing the vessels, and by causing blood to clot. Alum coagu- 

 lates casein and gelatin in the presence of an alkali. 



Action Internal. — Stomach and Intestines. — Enormous 

 doses of alum produce gastro-enteritis, while large doses 

 cause vomiting in carnivora. All the secretions are dimin- 

 ished in the alimentary canal, and constipation ensues, 

 unless the dose is excessive. Traces of alum are said to ap- 

 pear in the urine, but little is absorbed from the digestive 

 tract and systemic poisoning is not caused by the ingestion of 

 alum. Intravenous injection of salts of aluminum produce 

 vomiting, weakness, tremors, convulsions, paraplegia, diar- 

 rhea, and nephritis. Aluminum induces degeneration of 

 the brain and cord, and inflammation of the bowel and kid- 

 ney's in its elimination by these parts — like the other heavy 

 metals. Alum does not, therefore, occasion any stringent 

 action in the body outside of the digestive tract, and is ex- 

 creted by the bowels. 



Uses External. — Alum is employed mainly for local 

 surgical purposes. In arresting slight hemorrhages it may 

 be applied in saturated solution on absorbent cotton pledgets, 

 or in the form of burnt alum dusted upon the bleeding sur- 

 face. Epistaxis may be controlled by the injection of a 

 strong solution into the nostrils, or by insufflation of burnt 

 alum. Alum is sometimes used on granulating surfaces of 

 indolent ulcers, or wounds, as a slight caustic, stimulant and 

 antiseptic. It can be employed alone, or as a dusting powder, 

 containing: alum, 1 part; charcoal, 4 parts; and salicylic 

 acid, 2 parts. - Alumen exsiccatum will often prevent the es- 



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