486 VEGETABLE DKUGS 



Nervous System. — Toxic doses of quinine injected into 

 the carotid artery cause meningitis by direct irritation. In 

 man, ringing in the ears, fulness in the head, and slight deaf- 

 ness commonly follow a large medicinal dose (cinchonism). 

 Blindness also very rarely occurs in man after large doses.- 

 There are contraction of the retinal vessels and degenerative 

 changes in the retina and spiral ganglia of the cochlea, which 

 account for the loss of sight and hearing. There is some 

 clinical evidence that quinine in medicinal doses is a cerebral 

 stimulant, but there is no experimental proof of the fact. 



Spinal Cord and Nerves. — Quinine, as shown by experi- 

 ments conducted on the frog, lessens reflex activity after 

 small doses. This condition disappears on section of the 

 medulla. Toxic doses, however, cause permanent loss of 

 reflex excitabilty. The same, alkaloid first excites and then 

 paralyzes the peripheral sensory nerve endings. These effects 

 on the nervous system are not observed in mammals. Mus- 

 cular contractility stimulated by small and paralyzed by 

 poisonous doses of quinine. 



Uterus. — Quinine is thought by many to be an abortifa- 

 cient. There is no sufficient warrant for this conclusion. 

 There is, nevertheless, considerable testimony afiirming that 

 the alkaloid stimulates uterine contractions in inertia during 

 parturition, but at the same time increases the likelihood of 

 metrorrhagia. 



Kidneys, Metabolism and Elimination. ^Qui\\m.e less- 

 ens the secretion of uric acid and, to a somewhat less extent, 

 that of urea. Tissue waste must therefore be reduced. This 

 is in accordance with our knowledge of its power to lessen 

 oxidation and protoplasmic activity. It is curious to note 

 in this connection that the excretion of carbonic dioxide by 

 the lungs is not notably decreased. JSTinety per cent. %i qui- 

 nine is eliminated unchanged in the urine ; some is unab- 

 sorbed and passes away in the faeces. "While its excretion in 

 the urine begins soon after its ingestion, and lasts for some 

 days, the greater amount escapes within forty-eight hours. 



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