04 Botanic Drugs 



of neoplasms invading the floor of the skull, or by 

 syphilis, or in palsies from diphtheria toxins or 

 alcoholic excesses. Stimulating the vagus will not 

 help in any of these. Muscarine directly stimulates 

 the vagus nerve endings, and this inhibits the 

 action of the heart. Pilocarpine also does much the 

 same thing, affecting the involuntary muscles and 

 the autonomic and sympathetic nerve-endings; 

 and it also stimulates the plain muscle of certain 

 organs. Atropine, on the other hand, especially 

 in very small doses, annuls the inhibitory effect of 

 the vagus on the heart and the motor action, espe- 

 cially the involuntary. The action of anesthetics 

 on the heart is indirectly through the vagus. 



Now then, if arnica stimulates the vagus, the 

 analogies drawn above would lead one to expect it 

 to inhibit excessive muscular action of the heart, 

 to influence the involuntary muscles of the sphinc- 

 ters more particularly (as they are terminal in con- 

 trol), to stimulate the muscular coats of hollow 

 organs, and in a lesser degree to influence other 

 muscular structures. There would be very slight 

 influence upon the nervous system at large except 

 in full dosage. 



Therefore it would seem that we can rationally 

 look for an influence from arnica in traumatic strain 

 and in the overworked heart muscle, in atony of the 

 involuntary muscles, in sphincter incontinence, in 

 slight peripheral paralyses, and in muscular exhaus- 

 tion. 



How far this would be clinically borne out no 

 one man can say; but it is unfair to assert that the 

 empiric uses of arnica as a nerve stimulant, in sphincter 

 troubles, in myalgia and muscular strain, in optic 



