MOTOR EXCITANTS. 101 



3d, by lessening the frequency of the heartbeats; 

 4th, by correcting irregularity in the heart's action. 



Antidotes and Antagonists. — The best chemical 

 antidote is tannin, but the stomach-pump or emetics 

 must be used if possible, as the tannate of digitalin 

 is not entirely inactive. The best antagonist for 

 large doses is aconite, while opium is very service- 

 able to counteract the eJffects of its long-continued 

 use. 



Incompatihles are tannic acid, most of the iron 

 preparations, and cinchona. 



Therapeutics.— Enfeebled or irregular heart's 

 action during influenza; mitral disease; in hypertro- 

 phy of old horses when overworked, with weak pulse; 

 difficult breathing and dropsical effusions if resulting 

 from weak heart; palpitation from overwork or ex- 

 ertion after a full meal; pericarditis; endocarditis; 

 hemorrhage from lungs, stomach, or from large sur- 

 faces. In pneumonia in earlier stage, to help relieve 

 the local engorgement. In treating thick wind or 

 broken wind; coughs; combined with potassium ni- 

 trate or acetate as a diuretic; various dropsical afl:ec- 

 tions. The chief indications for the use of digitalis 

 are enfeebled, irregular, or irritable heart, deficient 

 arterial pressure, venous engorgement, and scanty 

 secretion of urine. Digitalis should not be used in 

 aortic disease or hypertrophy if pulse is strong, firm, 

 and regular. It has been recommended in purpura, 

 combined with copper sulphate in small doses. Ac- 

 cording to some authors digitalis is cumulative in ac- 

 tion, but personal experience fails to bear this out. 



