To  insure  quick  action  strychnin  is  preferably  administered  by
hypodermic  injection.  As  an  antidote  in  intoxication  with
paralyzing  poisons — general  anesthetics,  opium  and  its  salts,
choral  hydrate — it  acts  as  a  powerful  excitant.  Atropin  in  small
doses  increases  the  pulse  rate  as  a  result  of  its  inhibitory  influence
on  the  vagi  nerves;  it  apparently  antagonizes  the  action  of
morphin,  and  is  much  lauded  as  an  antidote  in  morphin  poison-
ing.
Paralysis,  or,  rather,  diminished  activity  of  the  vasomotor  cen-
ters, is  principally  accomplished  by  the  administration  of  the
nitrites.  Certain  halogen  substitution  compounds — chloroform,
chloral  hydrate,  etc. — have  a  pronounced  paralyzing  influence  on
the  nervous  sj^stem.  Their  action  on  the  vasomotor  centers  is  too
severe,  however,  and  consequently  they  are  not  used  for  such  pur-
poses. The  nitrites  dilate  the  peripheral  vessels,  especially  those
of  the  face  and  in  the  brain,  and  they  increase  the  heart  beat.
