276 
Fonmilas  for  Pharmaceutical  Preparations.  { 
Am.  Jour.  Pharm. 
June,  1891. 
ammonio-citrate  of  bismuth.  He  publishes  a  formula  for  elixir  of 
pepsin  and  bismuth,  of  which  one-half  is  this  elixir  of  pepsin  and 
the  other  half  elixir  of  bismuth,  so  that  the  finished  product  con- 
tains but  one  grain  each  of  saccharated  pepsin  and  ammonio-citrate 
of  bismuth,  which  is.  certainly  too  weak  in  pepsin  to  insure  any 
digestive  value. 
Mr.  Lloyd,  speaking  of  the  apparent  incompatibility  of  pepsin 
and  bismuth  and  the  value  of  substituting  acetic  acid  for  the  hydro- 
chloric acid  in  the  preparation  of  the  pepsin  solution  says:  "Thus 
permitting  it  to  be  mixed  with  the  bismuth  solution  with- 
out precipitation  of  bismuth  and  also  the  apparent  solution 
of  pepsin  in  the  presence  of  ammonio-citrate  of  bismuth.  We 
use  the  term  '  apparent  solution  of  pepsin?  for  although  the 
pepsin  undoubtedly  disappears  it  does  not  necessarily  follow  that  it 
dissolves  and  remains  active  pepsin.  Perhaps  it  is  so  modified  as  to 
be  devoid  of  digestive  value,  and  still  remain  dissolved.  Upon  the 
other  hand,  even  if  this  is  the  case,  it  is  barely  possible  that  such  a 
pepsin  is  only  paralyzed,  and  that  its  vitality  will  return  when  it  is 
taken  into  the  stomach." 
As  the  result  of  some  experiments  tried  in  1880,  the  writer 
was  led  to  use  citric  acid  as  a  solvent  for  the  pepsin  and  in  the  last 
edition  of  Parrish's  Treatise  on  Pharmacy  such  a  formula  is  published. 
As  the  citrate  of  ammonium  formed  upon  neutralizing  with 
ammonia  maintained  the  bismuth  in  solution,  preventing  the 
precipitate  which  usually  soon  forms  in  elixirs  made  with 
hydrochloric  acid,  it  was  considered  a  valuable  improvement, 
and  I  have  continued  its  use  since.  As  the  saccharated  pepsin  in 
the  market  has  increased  in  strength  during  the  past  10  years  it 
became  necessary  to  increase  the  amount  of  acid  used.  The  fol- 
lowing is  the  formula  I  would  suggest : 
Take  of 
Saccharated  pepsin,  .  .  . 
Citric  acid,  
Bismuth  ammonio-citrate, 
Stronger  white  wine,    .  . 
Spirit  of  orange,     .      .  . 
Sugar,  
640  grains 
120  " 
128  " 
8  fluid  ounces 
2  fluid  drachms 
4  troy  ounces 
of  each  a  sufficient 
quantity. 
