Am.  Jour.  Pharm. 
March,  1908. 
Therapeutic  Virtues  of  Digitalis. 
107 
DOES  DIGITOXIN  REPRESENT  THE  THERAPEUTIC 
VIRTUES  OF  DIGITALIS? 
By  Horatio  C.  Wood,  Jr. 
Associate  Professor  of  Pharmacology,  University  of  Pennsylvania. 
Within  the  last  year  or  two  there  has  been  a  revival  of  the  idea 
that  was  prevalent  a  generation  ago  that  digitoxin  might  be 
regarded  as  the  active  principle  of  digitalis.  In  1871  Nativelle 
was  awarded  the  Orfila  prize  for  the  discovery  of  the  active 
principle  of  digitalis.  Although  he  named  his  substance  digi- 
taline — under  which  title  it  is  still  recognized  by  the  French 
Codex — it  is  generally  regarded  as  identical  with  the  substance 
described  by  Schmiedeberg  as  digitoxin.  This  discovery  at- 
tracted much  attention,  and  naturally  the  crystalline  principle 
enjoyed  for  a  time  considerable  popularity.  It  failed,  however,  to 
sustain  its  place  as  a  practical  remedy,  and  its  use  outside  of  France 
was  almost  entirely  abandoned.  Recently,  however,  largely  on 
account  of  vigorous  advertising  by  certain  drug  manufacturers,  digi- 
toxin has  again  come  to  the  fore  as  representing  the  therapeutic 
properties  of  digitalis  in  a  compact  and  pure  form.  There  are  cer- 
tain observations  which  would  seem  to  throw  some  doubt  on  the 
justice  of  this  claim. 
In  the  first  place,  attention  may  be  called  to  the  small  amount,  ot 
digitoxin  found  in  digitalis  leaves  in  comparison  to  the  relative  tox- 
icity of  the  crude  drug  and  of  the  glucoside.  While  it  is  true  that 
digitoxin  is  the  most  actively  poisonous  of  the  principles  which 
have  so  far  been  discovered  in  digitalis,  it  seems  well  established 
that  the  dose  required  to  influence  the  circulation  is  disproportion- 
ately large  when  compared  to  the  amount  contained  in  the  leaves. 
Digitalis  is  a  drug  showing  such  great  variations  in  potency  that  it 
is  difficult  to  draw  accurate  conclusions  concerning  the  comparative 
physiological  activity  of  the  digitalis  leaves  without  a  simultaneous 
chemical  and  physiological  study  of  the  same  individual  specimen 
of  the  drug.  The  proper  method  to  arrive  at  the  conclusion  con- 
cerning the  quantitative  action  of  an  active  principle  would  be  to 
take  a  specimen  of  the  crude  drug,  determine  by  chemical  assay 
the  proportion  of  principle  present,  determine  by  physiological 
experiment  the  dose  of  the  crude  drug  required  to  kill,  also  the 
dose  of  the  principle  required  to  kill,  and  if  the  principle  accurately 
