Am.  Jour.  Pharm  | 
Oct.,  1877.  J 
The  Strength  of  Tinctura  Opii. 
511 
THE  STRENGTH  OF  TINCTURA  OPII. 
By  John  M.  Maisch. 
Attention  has  been  repeatedly  directed  to  the  variability  in  the  strength 
of  some  officinal  preparations.  Quite  a  number  must  be  expected  to 
differ  more  or  less,  even  if  prepared  by  precisely  the  same  process,  the 
variation  depending  upon  differences  in  the  constitution  of  the  crude 
drugs,  which  are  sometimes  very  considerable,  as  is  well  known  to  be 
the  case  with  opium.  Since,  however,  the  Pharmacopoeia  directs  dry 
opium  to  contain  not  less  than  10  per  cent,  of  morphia,  the  morphia 
strength  of  the  galenical  opium  preparations  should  not  fall  below  that 
standard  if  the  valuation  of  opium  was  not  neglected  by  many  pharma- 
cists. But  even  with  the  same  opium  there  is  a  possibility  of  arriving 
at  a  deficiency  in  strength,  amounting  to  from  6  to  10  per  cent.,  if  the 
drug  be  employed  merely  air-dry  or  be  previously  dried  at  or  near  the 
temperature  of  boiling  water  until  it  ceases  to  lose  weight.  Tincture 
of  opium  being  very  frequently  used  as  a  domestic  remedy,  some 
apothecaries  have  adopted  the  dangerous  practice  of  keeping  on  hand 
two  kinds,  one  made  according  to  the  Pharmacopoeia  formula,  intended 
for  dispensing  in  prescriptions,  and  another  weaker  tincture  for  ordinary 
sales.  The  latter  is  then  always  diluted,  and  occasionally  to  such  an 
extent  that  it  bears  little  resemblance  to  the  officinal  tincture  except  in 
name,  the  deficiency  in  color  being  compensated  by  the  addition  of 
licorice  or  caramel  ;  laudanum  sold  by  country  storekeepers  is  very 
generally  of  the  latter  class. 
The  strength  of  tincture  of  opium  as  ordinarily  sold  has  been  the 
subject  of  investigation  by  three  students  of  the  Philadelphia  College 
of  Pharmacy,  class  1876-77.  Mr.  Jos.  Stahle  Smith  merely  deter- 
mined the  amount  of  extract  left  on  the  evaporation  of  one  fluidounce 
of  the  tincture,  five  samples  giving  the  following  results  :  21  '5,  15,  11  *5, 
9*5  and  8  grains.  Each  fluidounce  represents  37*5  grains  of  dry 
opium,  which  on  an  average  yields  60  per  cent,  or  22*5  grains  of 
extract ;  the  presumption  therefore  is  that  of  the  five  samples  examined 
only  one  was  made  in  accordance  with  the  Pharmacopoeia. 
Mr.  Wm.  H.  Llewellyn  ascertained  not  only  the  amount  of  extract, 
but  separated  also  the  morphia  from  one  fluidounce  of  commercial 
laudanum,  using  for  the  latter  operation  a  modification  of  Staples'  pro- 
cess ;  his  results  were  as  follows  : 
