608 MEDICINES. 



Cocaine. 



This alkaloid is a very useful agent for producing local insen- 

 sibility to pain. If 5 or 6 drops of a solution of 1 grain of hydro- 

 chlorate of cocaine in 20 minims (or drops) of water be placed 

 on the surface of the eye, that part will, in from 5 to 10 minutes, 

 lose its sensibility to such an extent that it can be handled freely 

 without causing discomfort to the animal. We may use a solu- 

 tion of the hydrochlorate of cocaine of double that strength (say 

 10 grains in 100 minims of water) for hypodermic injections (p. 

 633) to deaden the feeling of a part. For the temporary re- 

 moval of lameness below the fetlock, or for finding if lameness 

 is due to pain above or below that part, Pader advises a sub- 

 cutaneous injection of cocaine on the outside and on the inside 

 of the leg, just above the fetlock, at the spot usually chosen 

 for the high operation of plantar neurectomy (p. 670) ; each in- 

 jection consisting of 2 grains of the hydrochlorate of cocaine 

 dissolved in 40 minims of distilled water, with a little bicar- 

 bonate of soda to neutralise it. The action of the cocaine is 

 increased by heating the solution to about 85° F. The amount 

 of cocaine in each injection might be safely increased to 3 

 grains. After these injections, the lameness disappears in 

 about ten minutes, and returns in about half an hour. For the 

 temporary relief of a case of painful cracked heels, it is well to 

 use a solution of 5 grains of the hydrochlorate in 20 drops of 

 oil of cloves. 



Some Continental veterinary surgeons speak highly of morphia 

 combined with cocaine for deadening pain in foot diseases, for 

 jeven a week or longer. The following subcutaneous injection, 

 which produces its effect in from 5 to 10 minutes, may be made 

 on each side of the plantar nerve (p. 670) : — • 



Hydrochlorate of cocaine ... ... 2|- grains. 



Morphia ... ... ... ... IJ grains. 



Distilled water ... ... ... ... H drachms. 



Cotton Wool, Antiseptic 



is prepared hj impregnating cotton-wool with various anti- 

 septics (boric acid, iodoform, corrosive sublimate, etc.), so 

 that layers of such material placed over a wound will protect the 

 part from the entrance of bacteria (p. 63). The same remark 

 applies to wood wool, and antiseptic gauze. These protective 

 agents can be obtained from any large chemist. 



