POTASSIUM CYANIDE 261 



staring; the pupils dilated; the teeth are clinched tight and covered with 

 frothy while the blood is of a very dark color. The treatment embraces 

 hydrogen peroxide by mouth; emptying the stomach by large doses of 

 promptly acting emetics, or by the stomach tube, or pump; atropine, 

 ether and brandy subcutaneously, and inhalations of ammonia, together 

 with artificial respiration, and hot and cold douches upon the chest. 

 Uses. — Prussic acid is indicated for three therapeutic purposes : 



1. To relieve gastric pain and vomiting, by its paralyzing action 

 upon the peripheral sensory nerves of the stomach. 



2. To stop coughing. 



3. To allay itching by means of its local, sedative action upon the 

 cutaneous sensory nerve-endings. 



As a medicine it is not of value, but is occasionally used in veter- 

 inary practice as a cough remedy, when the symptom is of reflex origin, 

 or is caused by chronic or verminous bronchitis ; and the acid is often 

 conjoined with chloroform, or opium, in some form. In verminous bron- 

 chitis the medicinal acid may be given by inhalation (5 ss. in § i. of 

 water) to calves, or internally (TTLxv.) to assuage coughing and to kill 

 the lung worms. Chloroform inhalations are more efficient. Prussic acid 

 is a dangerous remedy for use in relieving itching unless the dose is 

 carefully regulated. Ten minims of the acid, with gr. 14 of corrosive 

 sublimate to the ounce of water, is efficient in pruritus in the larger ani- 

 mals in amounts not larger than this for single applications, and not 

 larger than half this for the smaller patients. 



PoTASsii Cyanidum. Potassium Cyanide. K C N. (B. P.) 

 Synonym. — Cyanure de potassium, Fr. ; cyankalium, G. 



Derivation. — Made by heating together potassium ferrocyanide and carbonate. 



Properties. — White, opaque, amorphous pieces; or a white, granular powder, 



odorless when perfectly dry, but in moist air exhaling the odor of hydrocyanic 



acid. Taste sharp and alkaline, and in moist air the salt deliquesces. Reaction 



' very strongly alkaline. Solutions stain and destroy clothing. Soluble in about 2 



parts of wa'cer; sparingly soluble in alcohol. 



Dose.—H., gr.i-ii, (.06-.12) ; D., gr.J^, (.006). 



Action and Uses. — Potassium cyanide is transformed, in the stom- 

 ach and blood, into prussic acid, and resembles the latter in its action, 

 but is much slower. Death has been caused in man by 5 grains of the 

 salt ; by 1 to 2 drams in horses ; while 9 ounces were required to kill an 

 elephant. 



Pbunus Vikginiana. Wild Cherry. (U. S. P.) 

 Synonym. — :fi;corce de cerisier de Virginia, Fr. ; wildkirschenrinde, G. 

 The bark of the wild cherry, indigenous in the United States, contains a fer- 

 ment (emulsin) which, in the presence of water, acts on a glucoside (amygdalin, 

 C20 H27 N Oil) contained in the bark, with the formation of hydrocyanic acid, 

 glucose and a volatile oil. A fluidextract, infusion and syrup of prunus vir^ 

 giniana are official. The latter preparation is sometimes employed in cough 

 mixtures for dogs, on account of its sedative action. The entire value of the 

 drug depends upon the minute amount of prussic acid formed in it. The official 

 hydrocyanic acid is more reliable, but syrupus pruni virginianae (U. S. P.) may 

 be used as a vehicle for more efficient remedies, as follows: 



Digitized by Microsoft® 



