The  amount  of  cocaine  solution  to  be  injected  is  of
importitnce.  This  depends  upon  the  strength  of  the  solu-
tion, the  weight  and  species  of  the  animal,  and  the  seat  of
application.  A  solution  stronger  than  4  per  cent,  is  irritat-
ing to  the  eye.  The  stronger  cocaine  solutions  (5  to  10  per
cent.)  are  more  powerful  paralyzants  to  the  sensory  nerves^
and  are  advisable  when  they  can  be  used  with  safety,  but  a
1  or  2  per  cent,  or  even  a  much  weaker  solation,  will  ordin-


436


VEGETABLE  DIICGS


arily  produce  ansestliesiii  when  introduced  under  tbe  skin.
In  the  hqrae,  subcutaneous  injection  of  a  5  or  10  per  cent.
solution  may  be  made  to  tbe  amount  of  2  drachms  of  the
former,  or  1  dracbui  of  the  Idtter  solution  (cocaine,  gr.6).
Larger  doses  may  induce  restlessness,  excitement,  etc.,
which,  althongh  not  indicative  of  daupfer,  may  interfere  with
operatiye  procedures.  Wlieu  larger  quantities  are  desirable,
2^  drachms  of  a  4  per  cent  soUitiou,  or  5  drachms  of  a  2  per
cent,  solution,  may  be  employed  (equivaleut  to  6  gra.  of  the
alkaloid),  or  Schleich's  solution  may  be  utilized.  Not  mora
than  7  to  15  drops  of  a  10  per  cent  solution  should  be
injected  into  dogs.  This  is  equivalent  to  gr.|  and  gr.lj  of
the  alkaloid.  Three-quarters  of  a  grain  of  cocaine  is  a  safe
limit  of  dosage  for  small  dogs.  If  a  2  or  1  per  cent,  solution
is  employed,  30  M.  of  the  former,  or  15  M.  of  the ,  latter
solution  (equivalent  to  gr.^  of  cocaiue)  may  be  injected.
When  larger  amounts  of  the  ansosthetic  solution  are  in-
dicated for  dogs,  Schleich's  method  of  infiltration  ia  appro-
priate (infiltration  aniesthesia).
