COUNTER-IE EIT ANTS 669 



ally, and dilatation of vessels (when applied after the sub- 

 sidence of acute inflammation or in chronically inflamed 

 parts), with renewed activity of the circulation and conse- 

 quent absorption of inflammatory exudations. Further- 

 more, counter-irritants reflexly overcome spasm and pain 

 occurring in colic, by stimulating and replacing normal 

 peristaltic action in place of abnormal localized contractions. 

 In like manner they excite uterine contractions by stimula- 

 tion of the involuntary muscular fibres of the womb. 



INDICATIONS FOR COUNTER-IRRITANTS. 



1. To overcome congestion and inflammation in remote 

 parts. 



2. To promote absorption of inflammatory products 

 locally. 



3. To relieve pain. 



4. To stimulate the heart, respiration and nervous func- 

 tions. 



liuhefacients. — In this class are included the volatile 

 oils — turpentine, oil of wintergreen, etc. — alcohol, chloro- 

 form, balsams, resins, iodine, tincture of camphor, tincture 

 of cantharides, mustard, and heat. These agents are used 

 when it is desirable to stimulate the nervous system rapidly, 

 and to relieve pain and congestion. To attain this end, we 

 employ comparatively mild agents in order that we may 

 apply them over an extensive surface without causing seri- 

 ous or permanent results. Mustard is rubbed with warm 

 water into a thin paste (a sinapism), and rubbed over the 

 chest of horses iu congestion of the lungs, in acute bron- 

 chitis, or in the first stage of pleuritis, to obtund pain and 

 lessen congestion. Sinapisms also relieve obstinate cough, 

 revive failing respiration, and stimulate reflexly the vital 

 functions in collapse, shock and narcotic coma. Applied 

 over the cardiac region, they avert syncope. To assist the 

 action of mustard, we often cover the application with hot 

 blankets, and then with dry ones. Stimulating liniments 

 are sometimes preferred. One volume of oil of mustard 



