158 SYNOPSIS OF VETERINARY 



tinctura beeladonnae fouorum — Tincture of Belladonna 

 q )■' * Leaves. ( Sj^rengthjtg' per cent. ) 



Dose. — Dogs, 2 to 20 ms. 



unguentum belladonnas. — Strength 10 per cent of the ex- 

 tract. 



The preparations most commonly used are the extract, pow- 

 dered leaves, and fluid extract most of all. The root contains 

 the greatest per cent of atropine. 



ATROPINE SULPHAS— Sulphate of Atropine.— A 

 white crystalline powder, very soluble in water and alcohol; bella- 

 donna leaves contain 0.35 per cent and the root 0.2 to 0.6 per 

 cent. 



Dose. — Horse, yi to iy 2 grs. ; cattle 1 to 2 grs. ; dogs, i-igo 

 to 1-30 gr. ; }i gr. for horse when used with morphine. 



Composition. — The physiological activity depends on the 

 alkaloids ; atropine is found chiefly in the bark of the root, also 

 contains belladonine, hyoscyamine, an acid and coloring matter. 



Antagonists and Incompatiblcs. — Caustic alkalies ; antago- 

 nized physiologically by pilocarpine and physostigma throughout 

 almost the whole range of its influence, and opium within a cer- 

 tain limitation, prevents the respiratory failure, which is the cause 

 of death. 



Physiological Actions. — Belladonna is an irritant narcotic, 

 a mydriatic, an antispasmodic and anodyne. In small doses a 

 cardiac, respiratory and spinal stimulant ; in large doses a paralyz- 

 er of the secretory and motor nerve endings and a stimulator of 

 the entire sympathetic system. 



It produces dryness of the mucous membrane of the throat, 

 mouth, nose and larynx, and at first lessens the gastric and in- 

 testinal secretions, but soon reproduces them in large quantities. 

 It is anti-galactogogue, that is, it arrests secretion of milk. 



The heart rate is at first slowed, but soon becomes very rapid 

 and vigorous, the pulse being doubled in rapidity ; arterial tension 

 is raised and the circulation greatly increased ; this is accom- 

 plished by stimulation of the cardiac sympathetic, and paralyzing 

 the intracardiac inhibitory ganglia, thus stimulating the accelera- 

 tor apparatus while lessening the inhibitory. (Digitalis increases 

 both.) 



