. 97 



Internally. The local corrosive action of arsenic may be 

 employed in caries of the teeth to destroy the painful pulp before 

 stopping, a paste composed of 2 parts of arsenious acid, 1 part 

 of sulphate of morphia, and a sufficiency of creasote to make a 

 stiff compound, being placed in the cavity. 



Reaching the stomach in medicinal doses, the preparations 

 of arsenic do not combine with the albuminous contents like 

 mercury, but remain unchanged. They thus act upon the 

 mucous membrane, stimulating the nerves and vessels, causing 

 a sense of heat and hunger, and increasing the gastric function. 

 In these small doses arsenic is employed with advantage in 

 some cases of gastrjc dyspepsia, and a similar effect on the 

 duodenum makes it of some value in lienteric diarrhoea. If the 

 dose be increased, the stimulant action passes readily into 

 irritation of the stomach attended by pain, sickness, and 

 diarrho?a from intestinal excitement. These symptoms are to 

 be remembered only that they may be avoided, or arrested if 

 they should arise. 



2. ACTION ON THE BLOOD AND ITS USES. 



Arsenic enters the blood and combines with the corpuscles, 

 not with the serum, as an albuminate ; if in excess, it reduces 

 the number of the blood cells, as well as their oxygenating 

 power. It has been used with success in some forms of anaemia ; 

 but less frequently in idiopathic cases than where the corpuscles 

 and plasma have suffered from failure of nutrition elsewhere 

 (symptomatic anaemia), as in tuberculosis, malaria, gout, and 

 rheumatism. Alone or combined with iron, it has sometimes 

 an excellent effect in restoring the blood in such cases. 



3. SPECIFIC ACTION AND USES. 



Arsenic enters all the organs and tissues, but is not known 

 to combine with their albuminous constituents; it remains in 

 them for a short time only ; and is quickly excreted. During 

 this period, however, it distinctly influences metabolism. It 

 first reaches the liver, and diminishes the amount of glycogen 

 in it, so that it may be occasionally, but by no means often, 

 used with success in diabetes. In the other organs it interferes 

 similarly with metabolism, apparently (like phosphorus) through 

 the oxygenating process. An increased amount of nitrogenous 

 waste appears in the urine; the temperature rises; and the 

 excessive fatty product of the albuminous decomposition remains 

 unexcreted, constituting fatty degeneration. Short of this 

 effect, arsenic produces a wholesome increase of the metabolism, 

 or vital activity of all the organs, and is therefore given as a 

 general tonic, and as a valuable alterative in such classes of 

 H-8 



