304 INORGANIC AGENTS 



Poisonous quantities of these drugs diminish muscuLir 

 power, lessen reflex action and cause paralysis. Experi- 

 ments apparently show that acetanilid paralyzes the motor 

 nerves, antipyrin the motor nerve endings, while motor 

 depression seems to be of spinal origin in the case of 

 phenacetin. The brain is undoubtedly influenced by these 

 agents, as evidenced by coma and convulsions in poison- 

 ing, but exact knowledge is wanting in relation to the action 

 upon the brain. The functions of the cerebral cortex are 

 thought to be depressed by antipyrin, and the special senses 

 to be first stimulated and then paralyzed by this drug. 



Temperature. — Acetanilid, antipyrin and phenacetin are 

 essentially antipyretics. While they do not invariably lower 

 temperature, even in large doses in normal animals, they do 

 so very materially in animals suffering from fever. They 

 apparently depress the activity of the calorefacient centres 

 (probably in the corpora striata), and therefore diminish 

 heat production. Testimony is at variance in regard to 

 their action upon heat loss. They frequently induce diar- 

 phoresis, but it is generally accepted that heat dissipation 

 is increased to a greater extent than would be accounted for 

 by sweating, and that it occurs even when diarphoresis does 

 not take place. Wood teaches that these agents act solely 

 by lessening heat production, and this is no doubt their 

 main action. 



Respiration. — The respiratory functions are unaffected 

 by therapeutic doses of these medicines. In lethal doses 

 respiration is quickened, owing to the greater work thrown 

 upon the respiratory centre by the altered condition of the 

 blood, and this vital centre is ultimately paralyzed. 



Kidneys. — The drugs under consideration produce slight 

 diuresis in moderate medicinal doses. In poisoning, the 

 urine may become dark-colored by the hsematin escaping 

 from the disintegrated red blood corpuscles. Antipyrin 

 lessens the nitrogenous products of tissue waste in the 

 urine, and also diminishes the amount of that secretion. 

 Acetanilid, on the other hand, increases the excretion of urea. 



