Action of silver niteate 177 



the further action of the salt, so that lunar caustic is always 

 superficial and localized in its effect. Silver nitrate is tiie 

 caustic in most common use, since it produces a more healthy 

 condition in a granulating wound after its application and 

 separation of the eschar. Silver compounds are powerfully 

 antiseptic because silver itself is actively antiseptic and be- 

 cause the nitrate destroys germs in coagulating their pro- 

 teid_ protoplasm. In dilution, silver nitrate is stimulant, 

 astringent, antiseptic and caustic, according to its strength. 



Internal. — Silver nitrate is probably precipitated to a 

 cdnsiderable extent by the hydrochloric acid of the gastric 

 juice, as the chloride. Some of it is possibly converted into 

 the albuminate, and absorbed as such, when ingested for a 

 long period. Silver is deposited in the tissues in the form 

 of the oxide, causing dark staining of the skin in man. 

 These stains, occurring when silver nitrate ponies in direct 

 contact with the skin, can be removed by a solution contain- 

 ing potassium cyanide, 2i drachms; iodine, 15 grains; and 

 water, 3 ounces. Large doses of silver nitrate cause gastro- 

 enteritis with nervous symptoms — paralysis and convulsions 

 — and death from depression of the respiratory centres. 

 Common salt is the antidote, both externally and internally, 

 forming the insoluble chloride. In addition to salt, opium 

 and demulcents should be exhibited in acute poisoning. Sil- 

 ver nitrate in medicinal doses has probably a local stimula- 

 ting, astringent and alterative action on the mucous mem- 

 brane of the stomach ; to a less degree on the bowels. Elim- 

 ination may not take place at all — inert organic compounds 

 being deposited in various parts of the body — ^^or may occur 

 slightly from the epithelium of the digestive tract. A 

 chronic form of ppisoning by silver nitrate (argyrism), is 

 seen in man, following its continued use, and is accompanied 

 by pigmentation of the skin, marasmus, chronic indigestion, 

 with wasting of the testes and mammary glands. A similar 

 condition has been produced in animals, associated with 

 anorexia, weakness, anaemia and emaciation. 



Uses External. — An aqueous solution (gr.iii. to § i.) is 

 most valuable in treatment of catarrhal conjunctivitis, while 

 a stronger preparation (gr.x. to § i.) is employed for purulent 



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