12 VETERINARY MATERIA MEDICA. 



Cerebral-Excitants increase the functional ac- 

 tivity of the cerebrum without causing any subse- 

 quent depression or suspension of brain function, as 

 camphor, cannabis indica, valerian, cocaine. 



Cerebral Depressants suspend or lower the 

 functions of the higher brain after a preliminary 

 stage of excitement. This group includes the nar- 

 cotics, the general ansesthetics, the hypnotics, and 

 some of the antispasmodics. The action of these is 

 first to stimulate the cerebral functions and then after 

 a time to produce stupor, coma, and insensibility, as 

 alcohol in large doses, opium, bromides, chloral, 

 etc. 



Deliriants excite the functional activity of the 

 brain to such a degree as to disorder the mental facul- 

 ties. This produces intellectual confusion, loss of 

 will power, delirium, and sometimes convulsions. 

 These agents include belladonna, stramonium, hyos- 

 eyamus, chloral, etc. 



Narcotics are agents which lessen the relationship 

 of the individual to the outside world (Brunton). 

 The}^ at first excite the higher brain, but soon cause 

 a profound sleep, characterized by increasing stupor; 

 and if the dose has been large enough, coma, insen- 

 sibility, and finally death by paralysis of the centres 

 of respiration and other functions of organic life. 

 The chief narcotics are opium, cannabis indica, alco- 

 hol, belladonna, chloral, chloroform, ether, etc. 



Hypnotics are agents which produce sleep without 

 causing any preliminary cerebral excitement, as the 

 bromides, paraldehyde, chloralamid, etc. 



