Am.  Jour.  Pharm. 
Jan.,  1886. 
Several  Official  Ointments. 
5 
petrolatum  together,  an  excellent  carbolic  ointment  results.  A  desir- 
able product  is  obtained  by  melting,  one  troy  ounce  of  stearic  acid 
with  one  troy  ounce  of  petrolatum,  then  gradually  adding  seven  troy 
ounces  more  of  petrolatum,  while  maintaining  the  heat,  to  insure 
perfect  fusion.  To  this  mixture  one  troy  ounce  of  carbolic  acid  is 
added,  either  previously  fused  or  in  detached  crystals,  then  stirred 
until  thoroughly  mixed,  and  finally  permitted  to  cool  during  occa- 
sional stirring. 
The  Pharmacopoeia  has  now  adopted  the  superior  thiosulphate 
process  for  preparing  ointment  of  potassium  iodide.  But  the  employ- 
ment of  benzoinated  lard  is  not  only  unnecessary  and  useless,  but 
possibly  detrimental.  Another  error  was  committed  in  using  an 
insufficient  quantity  of  water  for  permanently  dissolving  the  salt. 
Although  a  barely  ample  amount  of  hot  water  is  directed,  nevertheless 
the  solution  of  the  salt  on  cooling  deposits  more  than  half  of  it  in 
crystals.  Under  the  circumstances,  it  would  have  been  much  better 
to  incorporate  the  saline  mixture  dry  and  finely  powdered.  Properly, 
however,  the  salt  should  be  in  perfect  and  permanent  solution.  The 
writer  has  always  noticed  that  when  lard  alone  is  used  in  making  this 
ointment,  a  speedy  and  decided  disintegration  of  the  fatty  excipient 
results.  A  small  proportion  of  white  wax  will  always  prevent  this, 
and  add  to  the  general  preservation  of  the  ointment. 
It  was  ascertained  that  petrolatum  wax  (paraffin  wax)  yields  a 
smoother,  even  whiter,  and  otherwise  stabler  product.  The  writer 
now  prepares  this  ointment  by  fusing  together  three-fourths  of  a  troy 
ounce  of  petrolatum  wax  and  three-fourths  of  a  troy  ounce  of  lard, 
then  gradually  adding  four  and  a  half  troy  ounces  more  of  lard  and 
setting  the  melted  mixture  aside.  One  troy  ounce  of  potassium 
iodide  and  twenty-four  grains  of  sodium  hyposulphite  (thiosulphate) 
are  then  dissolved  in  one  fluid  ounce  of  water.  This  solution  is  now 
thoroughly  incorporated  with  the  fatty  excipient,  previous  to  its  com- 
plete congelation.  When  it  is  deemed  desirable  to  use  petrolatum  in 
preparing  this  ointment,  the  white  article  is  preferable.  The  saline 
solution  is  not  miscible  with  petrolatum  alone.  A  small  proportion 
of  lard,  however,  effects  a  ready  mixture.  The  writer  has  found 
stearic  acid  more  adaptable.  Too  large  a  proportion  of  this  again 
prevents  a  proper  union.  A  slight  discoloration  of  the  ointment  re- 
sults from  the  liberation  of  a  trace  of  iodine.  The  presence  of  a 
small  amount  of  sodium  hyposulphite  gives  a  product  of  superior 
