Ve'braary,Pih9air4m'}     Standardization  of  Heart  Tonics.  69 
weight  of  the  cat.  This  amounts  to  0.1  milligramme  of  the  Ouabain 
and  the  number  of  "  cat  units  "  in  one  cubic  centimetre  of  the  prep- 
aration being  tested  is  computed  from  the  data  obtained.  Eckler  25 
has  reported  serious  disadvantages  to  this  method,  and  it  is  doubtful 
if  it  will  ever  have  the  popular  favor  the  other  two  methods  enjoy. 
Factors  Relating  to  the  Standardization  of  Digitalis. 
It  may  easily  be  seen  that  the  last  word  has  not  been  said  in 
regard  to  the  standardization  of  Digitalis  and  this  unsettled  condition, 
in  its  standardization,  is  certain  to  prevail  until  the  therapeutic  uses 
and  chemistry  of  the  drug  are  agreed  upon. 
It  is  true  that  some  fault  can  be  found  with  the  methods  we  have 
outlined  and  no  doubt  many  factors  will  soon  be  eliminated. 
At  the  present  time,  it  is  possible  to  determine  by  physiological 
tests  with  reasonable  accuracy  the  variability  of  the  crude  drug,  the 
stability  of  its  preparations,  and  to  prepare  preparations  of  con- 
siderable uniformity.26 
Other  Heart  Tonics. 
What  has  been  said  in  regard  to  the  methods  used  for  standard- 
izing Digitalis  applies  also  to  preparations  of  Strophanthus,  Squill  and 
Convallaria.  Strophanthus  seems  to  be  more  certain  in  its  action 
than  digitalis  and  can  also  be  advantageously  tested  by  the  blood- 
pressure  method  upon  dogs. 
Cactus  grandiHorus  has  long  been  used  empirically  with  appa- 
rently favorable  results,  yet  competent  pharmacologists  have  reported 
that  it  has  no  action  analogous  to  digitalis 27'28.  Graeber 29  has 
recently  reported  the  presence  of  both  alkaloids  and  glucosides  in 
this  drug  and  publishes  experiments  on  frogs  which  "  indicate  that 
Cactus  grandiflorus  actually  is  possessed  of  an  action  upon  the  heart 
such  as  belongs  to  the  substances  of  the  digitalis  group."  In  all  his 
frog  experiments  the  frequency  of  the  pulse  was  reduced  and  the 
systole  strengthened. 
Sparteine  sulphate  is  considered  a  drug  of  mediocre  importance 
as  a  "  heart  tonic,"  yet  Pettey  30  considers  that  Sparteine  is  unappre- 
ciated because  it  is  not  given  in  sufficient  doses.  He  recommends  the 
use  of  2  grain  doses  as  a  true  and  reliable  heart  tonic,  an  excellent 
non-irritating  diuretic  and  states  that  this  dose  is  entirely  free  from 
untoward  or  objectionable  effects. 
