1 8  A  Study  of  Cannabis  Americana 
poses,  in  order  that  we  may  know  exactly  how  they  behave  under 
given  conditions.  After  the  animals  have  been  finally  selected  and 
found  to  respond  to  the  standard  test  dose,  «oio  per  kilo,  they  are  set 
aside  for  this  particular  work,  care  being  taken  to  have  them  well  fed 
well  housed,  and  in  every  way  kept  under  the  best  sanitary  condi- 
tions. Usually  we  have  found  it  desirable  to  keep  two  or  more  of 
the  approved  animals  on  hand  at  all  times,  so  there  may  not  be 
delay  in  testing  samples  as  they  come  in. 
In  applying  the  test,  the  standard  dose  is  administered  internally 
in  a  small  capsule.  The  dog's  tongue  is  drawn  forward  between  the 
teeth  with  the  left  hand  and  the  capsule  placed  on  the  back  part  of 
the  tongue  with  the  right  hand.  The  tongue  is  then  quickly  released 
and  the  capsule  swallowed  with  ease.  In  order  that  the  drug  may 
be  rapidly  absorbed,  food  should  be  withheld  twenty-four  hours 
before  the  test  and  an  efficient  cathartic  given,  if  needed. 
Within  a  comparatively  short  time,  one  to  two  hours,  the  dog 
begins  to  show  the  characteristic  effects  of  the  drug :  First  a  stage 
of  excitability  is  noticed,  followed  sooner  or  later  by  a  condition  of 
incoordination,  the  animal  behaving  as  though  intoxicated.  Expe- 
rience is  necessary  on  the  part  of  the  observer  to  determine  just 
when  the  physiological  effects  of  the  drug  begin  to  manifest  them- 
selves, as  there  is  always,  as  in  the  case  of  many  chemical  tests,  a 
personal  factor  to  be  guarded  against.  The  dogs  must  be  kept  per- 
fectly quiet  and  watched  without  attracting  their  attention.  The 
influence  of  the  test  dose  of  the  unknown  drug  is  carefully  com- 
pared with  the  same  dose  of  the  standard  preparation  administered 
to  another  test  dog  at  the  same  time,  under  the  same  conditions. 
Finally,  the  dogs  become  sleepy,  the  observations  are  recorded  and 
the  animals  returned  to  their  quarters. 
The  second  day  following,  the  two  dogs  are  reversed,  i.  e.,  the 
animal  receiving  the  test  dose  of  the  unknown  receives  the  test 
dose  of  the  known,  and  vice  versa,  and  a  second  observation  made. 
If  one  desires  to  make  a  very  accurate  quantitative  determination, 
it  is  advisable  to  use  not  two  dogs  but  four  or  five,  and  study  the 
effects  of  the  test  dose  of  the  unknown  in  comparison  with  the  test 
dose  of  the  known  upon  each.  If  the  unknown  is  below  standard 
activity,  the  amount  should  be  increased  until  the  effect  produced  is 
the  same  as  for  test  dose  of  standard.  If  the  unknown  is  above 
strength,  the  test  dose  is  diminished  accordingly.   From  the  dose  of 
Am.  Jour.  Pharm, 
January,  19C8. 
