466 VEGETABLE DBUGS 



Circulation. — Veratroidine mainly influences the cardiac 

 inhibitory apparatus. When artificial respiration is practised, 

 so that the effect of the substance on the respiratory centres 

 will not overcome the action on the circulation, it is found 

 that the alkaloid slows the heart's action in moderate doses 

 by stimulating the pneumogastric centres. Large toxic 

 doses, on the other hand, paralyze the vagus nerve endings 

 in the heart, and the cardiac pulsations therefore become 

 very frequent. The vasomotor centres are uninfluenced by 

 ordinary quantities of veratroidine. 



Bespiration. — The depressing action of veratroidine on 

 the respiratory functions is more marked than that exerted 

 on the heart, so that, unless artificial respiration is sustained, 

 asphyxia supervenes, and this leads to vasomotor spasm and 

 great rise of bloo'd pressure. Death ensues from respiratory 

 failure. 



Nervous System. — The influence of veratroidine upon 

 the nervous system is similar to that of jervine, but the 

 spasmodic phenomena are not so prominent. 



VEEATEUM. 



Action Internal. — The action of the drug is a resultant 

 of the action of veratrine*, jervine and veratroidine. 



Circulation. — The most noteworthy therapeutic value of 

 veratrum viride depends upon its effect on the circulation. 

 It first lowers the force (jervine), and, if continued, the fre- 

 quency (veratrine*, protoveratrine*, veratroidine and jer- 

 vine) of the pulse, and also reduces vascular tension 

 (jervine). Veratrum is considerably more powerful than 

 aconite, which depresses the action of the heart, but does 

 not directly lessen arterial action. Veratrum is, however, 

 inferior to aconite for general purposes, as ' it does not 

 possess the anodyne, diarphoretic, or diuretic properties 

 peculiar to the latter drug. 



The temperature is reduced several degrees by large 

 doses of veratrum. 



Toxicology. — The symptoms exhibited in veratrum 

 poisoning are : salivation, vomiting, or attempts at vomiting, 



* See t). 468. 



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