368 
Standardisation  of  Drugs. 
(  Am.  Jour.  Pharui. 
\     August,  1910. 
1902,  p.  415).  Digitalis  leaf,  675;  digitoxin,  8.7;  strophanthus  (5 
per  cent,  tincture),  5.625 ;  strophanthin,  0.5  (c.f.  Table  I)  ;  adonidin, 
4.  They  state  in  their  conclusions :  Determinations  of  the  relative 
strengths  of  different  samples  of  the  same  drug  may  be  made  with 
precision  sufficient  for  practical  purposes  by  physiological  experi- 
ments on  animals,  but,  as  might  be  expected,  the  relative  medicinal 
strength  of  different  drugs  cannot  be  correctly  inferred  from  the 
observation  of  a  single  symptom  produced  in  an  animal  like  the  frog. 
They  found  differences  of  less  than  ten  per  cent,  in  duplicate 
experiments. 
A  further  disadvantage  in  the  use  of  the  frog  is  due  to  the 
differences  in  the  rate  of  absorption  of  the  different  digitalis  bodies. 
Even  such  closely  related  bodies  as  amorphous  and  crystalline 
strophanthin  differing  markedly  in  this  respect.  Famulener  and 
Lyons  have  also  called  attention  to  this  objection. 
We  have  attempted  to  compare  the  results  which  those  authors 
obtained  when  working  with  the  frog  with  those  obtained  bv  our- 
selves with  the  cat,  but  the  differences  are  evidently  due  to  differ- 
ences in  the  animals  and  not  to  the  limits  of  error. 
Focke  (Pharm.  Zeitung,  vol.  54,  Xo.  68)  says  that  after 
further  consideration  of  the  subject  he  believes  that  it  is  not  feasible 
to  accustom  physicians  to  thinking  and  calculating  the  strength 
of  digitalis  preparations  in  frog  units. 
There  are  many  reasons  for  believing  that  the  action  of  the  digi- 
talis bodies  on  the  cat's  heart  is  a  better  index  than  that  on  the 
frog's  of  their  effect  on  the  human  heart.  Man  absorbs  strophan- 
thin much  as  the  cat  and  dog  do,  and  the  effects  are  much  the  same. 
Koppe's  experiment  in  which  2  mgs.  of  digitoxin  taken  in  dilute 
alcohol  caused  serious  symptoms,  shows  the  possibility  of  rapid 
absorption  and  unusual  action;  on  the  other  hand,  we  know  of  in- 
stances in  which  2  mgs.  of  crystalline  ouabain  have  been  adminis- 
tered intravenously  without  causing  ill  effects,  though  that  is  25  per 
cent,  of  the  theoretically  fatal  dose. 
The  cat  is  the  least  resistant  to  strophanthin  and  ouabain  of  all 
the  animals  which  we  have  examined,  but  the  rat  and  mouse  alone, 
so  far  as  our  experience  goes,  are  very  resistant.  There  are  marked 
differences  in  the  subcutaneous  and  intravenous  doses  for  the  rabbit 
and  some  other  animals,  but  not  for  the  cat  and  the  dog. 
The  various  digitalis  bodies  are  the  subject  of  clinical  investiga- 
tion at  the  present  time  in  certain  of  the  hospitals  in  New  York, 
