Am.  Jour.  Pharm.  \ 
February,  1897.  / 
Correspondence. 
101 
garded  as  alike  in  therapeutic  effect,  if  the  precipitate  contains  none 
of  the  useful  medicinal  constituents. 
These  propositions  are  almost  self-evident,  and  will  probably  not 
be  gainsaid.  But  it  is  a  well-known  fact  that,  in  many  cases,  the 
dilution  of  a  fluid  extract  produces,  sooner  or  later,  more  or  less 
precipitation.  And  as  it  is  not  at  all  practicable  to  classify  drugs 
into  groups  representing  such  as  will  or  will  not  yield  precipitable 
fluid  extracts,  though  it  is  possible  to  mention  some  from  which  no 
precipitate  is  derived,  it  seems  to  me  unwise  to  give  a  general  en- 
dorsement to  the  practice  of  preparing  tinctures  from  fluid  extracts, 
at  least  at  the  present  time,  and  in  the  present  state  of  our  knowl- 
edge. If  the  manufacturing  houses  could  put  on  the  market  fluid 
extracts  of  full  official  strength,  made  with  menstrua,  the  further 
addition  of  which  would  cause  no  precipitate,  or  at  most  only  one 
known  or  guaranteed  to  be  inert,  the  practice  might  be  approved. 
But  as  this  is  not  the  case,  nor  likely  to  happen  in  the  near  future, 
no  general  license  to  make  tinctures  from  fluid  extracts  should  be 
given.  On  the  other  hand,  if  a  pharmacist  has  the  knowledge  and 
ability  to  examine  and  assay  his  preparations,  and  is  willing  to  as- 
sume full  responsibility  for  the  quality  of  the  medicines  he  dispenses, 
he  should  have  full  liberty  as  to  how  he  arrives  at  any  preparation, 
say  at  a  tincture,  and  it  is  then  immaterial  whether  he  prepares  it 
from  the  fluid  extract  or  the  drug.  I  would,  therefore,  offer  as  a 
third  proposition  the  following  : 
(3)  The  practice  of  preparing  tinctures  from  fluid  extracts,  in  all 
cases  where  dilution  causes  obvious  physical  changes  (such  as  pre- 
cipitation, gelatinization,  etc.),  is  not  to  be  recommended  for  general 
use,  but  may  be  adopted  in  cases  of  necessity  or  urgency,  when  a 
prescription  calls  for  the  tincture  of  a  drug  of  which  only  the  fluid 
extract  is  available  or  obtainable. 
Now  as  to  the  labels  you  sent  me.  To  judge  from  experience,  I 
should  say  that  no  trouble  will  be  encountered  in  preparing  a  tinct- 
ure from  the  fluid  extracts  of  aconite  and  ipecac.  But  it  is  probable 
that  some  precipitate  will  form  in  the  case  of  belladonna  leaves  and 
coca  leaves,  particularly  as  different  persons  are  apt  to  use  different 
menstrua,  in  spite  of  your  direction.  Still,  we  should  not  pay  any 
attention  to  what  may  happen  if  your  directions  are  disobeyed.  If 
it  can  be  shown  that  the  precipitate  in  these  cases  is  free  from  alka- 
loids, there  can  be  no  objection  raised  against  the  method. 
