Am.  Jour  Pharm. 
June,  1898. 
Sodium  Phosphate  Solution. 
305 
phia  Hospital  a  formula  which  he  thinks  overcomes  such  an  objec- 
tion, if  it  exists.  The  following  is  the  formula  used,  slightly  in- 
creased in  proportion  of  ingredients  over  original  formula  : 
Sodium  phosphate,  dried  and  powdered  3  ozs.  (Troy)  96  grs. 
Acid,  phosphoric  (50  per  cent.)  il/2  fl.-ozs.  (921  grs. ) 
Water,  a  sufficient  quantity  to  make  8  fluidounces. 
Dissolve  the  solids  in  the  water,  which  has  had  the  acid  previously  added  to 
it,  and  filter  through  paper. 
Especial  care  should  be  taken  to  use  the  nearly  anhydrous  "  dried 
and  powdered  "  sodium  phosphate, and  not  the  "granular"  salt  with 
its  57  per  cent,  of  water,  or  the  resulting  preparation  will  be  exces- 
sively, and  possibly  dangerously,  acid.  If  desired,  the  85  per  cent, 
acid,  of  the  U.S.P.,  '90,  may  be  used. in  place  of  the  50  per  cent., 
employing  a  proportionately  less  quantity  (i.  e.,  542  grains).  The 
85  per  cent,  acid  should  be  always  weighed,  however,  and  not  meas- 
ured, in  order  to  ensure  greater  accuracy.  Its  great  density  increases 
possibility  of  error  in  measuring,  unless  checked  by  weighing. 
The  dose  of  this  preparation  of  sodium  phosphate  is  one  to  two 
teaspoonfuls  in  a  wineglassful  or  more  of  water,  preferably  hot,  three 
times  a  day,  one  hour  before  eating.  If  taken  cold  it  may  be  made 
very  acceptable  by  the  addition  of  about  ten  grains  of  sodium  bicar- 
bonate (baking  soda),  when  effervescence  of  carbonic  acid  gas  en- 
sues, and  a  grateful  vichy-like  solution  results.  If  the  volume  of  the 
dose  be  objected  to,  a  teaspoonful  or  more  of  the  solution  diluted 
with  an  equal  volume  of  water  may  be  given,  followed  by  the  wine- 
glassful  or  more  of  water.  But,  on  therapeutic  grounds,  a  relatively 
larger  volume  of  water  should  always  be  given  coincidentally  with 
the  dose. 
As  thus  made,  the  solution  of  sodium  phosphate  is  a  clear,  trans- 
parent, faintly  acid  liquid,  slightly  heavier  than  official  syrup,  having 
a  cooling  saline  taste,  mixing  with  water  unchanged  in  all  propor- 
tions, remaining  liquid  at  ordinary  temperature,  and  yielding  to  each 
fluidram,  on  evaporation  to  thorough  dryness,  about  thirty  grains 
of  anhydrous  salts. 
In  the  making  of  the  solution,  the  writer  believes  that  the  follow- 
ing chemical  re-action  takes  place,  in  part  : 
Na2HP04  +  H3P04  =  2NaH2PO, 
141-8  97-8  2396 
In  other  words,  the  official  sodium  acid  phosphate  becomes  par- 
