394  ■      Stability  of  Digitalis  Leaf  Extracts.     [  ^7une^^92'o: 
THE  STABILITY  OF  DIGITALIS  LEAF  EXTRACTS.  THE 
INFUSION  (Second  Paper). 
By  Clayre  a.  Pomeroy  and  Frederick  W.  Heyl, 
kalamazoo,  michigan. 
In  a  previous  paper^  the  deterioration  of  alcoholic  digitalis 
extracts  was  discussed  and  a  rather  rapid  rate  of  deterioration  was 
established.  A  study  of  the  stability  of  aqueous  solutions  is  impor- 
tant because  of  the  wide  use  of  the  infusion  in  practical  therapeutics. 
It  is  also  interesting  to  observe  the  behavior  of  such  solutions  because 
of  the  fact  that  most  of  the  investigators  to  whom  we  owe  our  present 
information  concerning  the  chemistry  of  the  leaf  have  used  pro- 
cesses involving  the  use  of  aqueous  solutions. 
Infusion  of  digitalis  is  the  oldest  of  the  galenical  preparations 
of  this  drug,  and  was  in  fact  employed  by  Withering,  to  whom  we 
owe  the  introduction  of  the  drug  to  modern  practice.  He  began  to 
use  it  as  a  diuretic  and  the  dose  used  is  stated  as  1-3  grains  twice 
a  day  or  the  equivalent  amount  of  infusion  (1-3  drachms  of  1.5  per 
cent,  infusion). 
Aside  from  the  clinical  value  of  the  infusion,  which  it  is  not 
our  purpose  to  discuss,  our  brief  investigation  points  out  conclusively 
that  in  the  modern  evolution  of  pharmacy  we  have  lost  some  of  the 
unique  powers  of  observation  which  the  pharmacists  of  the  i8th 
and  early  part  of  the  19th  century  had  developed  to  such  a  degree 
that  their  personal  interest  could  be  relied  upon  in  the  matter  of 
collecting  and  selecting  drugs.  The  olden-time  pharmacist  knew 
his  digitalis  and  the  activity  of  the  infusion.  The  modern  phar- 
macist must  necessarily  rely  upon  the  assistance  of  the  pharma- 
cologist in  this  matter.  During  the  interval  between  the  old  period 
and  the  time  when  complete  scientific  standardization  shall  be  used, 
such  problems  as  that  presented  by  infusion  of  digitalis  must  prove 
a  stumbling  block  to  clinical  progress. 
We  have  recently  been  required  to  answer  a  large  number  of 
inquiries  on  the  part  of  clinicians  concerning  the  strength  and  sta- 
bility of  the  infusion.  Not  only  do  we  find  a  wide  variation  in  the 
strength  of  various  samples  of  leaves,  but  the  instability  of  the  in- 
fusion itself  lends  further  variability  to  this  preparation.  The  phar- 
macist relies  upon  indirect  sources  of  supply  for  his  crude  drug,  and 
^  Am.  J.  Pharm. ,gi:  425,  1919. 
