ACTION OF TOBACCO AND NICOTINE 40i 



nerves, so that iu poisoning convulsions are succeeded by 

 paralysis. The cerebrum is unaffected ; likewise the 

 muscles, but the function of the sensory nerves is somewhat 

 depressed. 



Respiration. — The respiration is depressed in some un- 

 known manuer. 



Eye. — Nicotine, in moderate toxic doses, or when applied 

 locally, contracts the pupil. This action is exceptional for 

 a member of the solanacese. Myosis is produced in the eye, 

 recently removed from the head, so that the action must 

 be a local one. It is due to paralysis of the endings 

 of the cervical sympathetic nerve and, probably, to 

 stimulation of the peripheral oculomotor nerve termination 

 as well. 



Elimination. — Nicotine is eliminated in the urine, which 

 is increased in amount thereby. 



Toxicology. — Nicotine is one of the most powerful and 

 rapidly acting poisons. When swallowed, it causes, in ani- 

 mals, local irritation and pain in the throat and stomach; 

 muscular tremors and weakness, on account of which the 

 animal falls. These symptoms are followed, first, by severe 

 tonic and clonic convulsions, and then by abolition of volun- 

 tary motion and quietude. The pupils are contracted, and 

 there is vomitiug (in the case of some animals), purging and 

 micturition. The respiration is at first shallow and rapid, 

 but becomes weaker and slower, and death occurs from 

 respiratory failure and general collapse. The pulse is 

 primarily slow and intermittent, but later becomes rapid. 

 The treatment of poisoning consists in evacuation of the 

 stomach ; the use of tannic acid ; respiratory and heart 

 stimulants, as strychnine, atropine, and alcohol; together 

 with external heat and artificial respiration. The minimum 

 lethal dose is about one drachm of tobacco, or one minim of 

 nicotine, for small dogs. For horses, five to ten drops of 

 nicotine or one-half pound of. tobacco. 



Uses. — Tobacco is not a particularly valuable medicinal 

 agent. Its internal action is often violent, and causes great 



