Botanic Remedies 93 



Thymol itself is a phenol nearly insoluble in water. 

 Aristol is a dithymol diiodide soluble in fatty oils 

 and a valuable indirect antiseptic in 10 per cent 

 ointment or suppository. It may also be applied 

 in powder in any proportion. 



ARNICA 



Arnica flowers are official in all but the Hungarian 

 standards, the leaves in the Croatian and Mexican 

 standards, and the root in the Austrian, Croatian, 

 Italian, Japanese, Serbian, and Spanish standards; 

 yet it is a drug imperfectly understood. In large 

 doses it is a toxic gastro-intestinal irritant which 

 causes a fall in temperature, motor and sensory 

 paralysis, collapse and death. In moderate doses 

 it slows the pulse, slightly raises blood-pressure, and 

 stimulates the vagus nerves (Wilcox). 



Externally arnica was formerly much in use, but 

 in many persons its application gives rise to cutane- 

 ous inflammation of an erysipelatous type and even 

 to constitutional symptoms. It is now little em- 

 ployed externally. 



What rational indication there may be for the 

 "average dose" of 15 grains of the U. S. P. VIII is 

 a mystery I have not been able to solve. The Ninth 

 Revision gives the average dose of the tincture 

 (20%) as 15 minims, which is more reasonable. 



In small doses arnica has been recommended in 

 a host of conditions, especially those requiring 

 stimulation of the brain and spinal nerves. It must 

 be admitted that the drug does stimulate the vagus 

 nerve. Now what is the connection here, and what 

 is the pharmacology of the vagus? 



The vagus nerve may be involved as the result 



