154 SYNOPSIS OF VETERINARY 



Dose. — Horses, 2 drs. to 1 oz. ; dogs, 1 m. to 20 minims, bet- 

 ter than the Fid. Ext 



inFusum digitalis — Infusion of Digitalis, (i/^^.) 



Dose. — Dogs, y 2 to 4 drachms ; horses, 2 to 6 ounces. Best 

 for diuretic action. 



digitalinum — Digitalin. 



Dose. — Cattle, 1 to 2 grs. ; horse, y 2 to 1 gr. ; dogs, 1-100 to 

 1-30 gr. 



digitalis folia — Powdered Leaves of Fox-Glove. — Best 

 torm for heart tonic. 



Dose. — Horse, 20 grs. to 1 dr. ; sheep and pigs, 5 to 15 grs. ; 

 cattle, 1 to 2 drs. ; dogs, 34 to 3 grs. 



Digitalis is an unreliable drug, due perhaps to the variable 

 quality of the crude drug. 



Strophanrhus is more reliable and a nicer acting drug. 



Composition. — Digitalis contains five principles, but no al- 

 kaloids. They are : Digitalin, Digitoxin, Digitalein, Digitin, 

 Digitonin. These are glucosides. 



Antagonists and Incompatibles. — Cinchona preparations, ace- 

 tate of lead, sulphate and tr. chloride of iron are chemically in- 

 compatible. Tannic acid and preparations containing it dimin- 

 ish the physiological action of digitalis. Opium aconite, lobelia 

 and the cardiac paralyzers, antagonize some but not all of its 

 actions. The most complete physiologic'ol antagonist and best 

 antidote is Saponin. 



{SAPONIN. — Is a glucoside, occurs as a white amorphous 

 powder. Dose for man 1-10 to 1-5 gr. ; horse, 1^/2 to 3 grs.) 



Aconite antagonizes the cardiac action of digitalis, and mor- 

 phine also to a less degree. 



Synergist. — Cold, ergot, and belladonna increase its activity. 



Physiological Actions. — It is a cardiac and vascular tonic 

 and stimulant, a motor excitant, paralyzant, anaphrodisiac, (low- 

 ers sexual desire) ; it is an indirect diuretic and an emetic, irritates 

 the mucous membrane. 



On the Heart. — The' heart is slowed but the force is in- 

 creased ; digitalis stimulates the cardiac motor ganglia, the in- 

 hibitory apparatus and the vaso-motor centers, contracting the 

 arterioles and thereby greatly raising the arterial tension ; full 

 doses exhaust and paralyze the heart. 



