Am.  Jour.  Pharm. 
July,  1889. 
Glycerites  of  Ferrous  Salts. 
367 
GLYCERITES  OF  FERROUS  SALTS.1 
By  Charles  Arthur. 
Liquid  preparations  of  ferrous  salts,  such  as  the  syrup  of  iodide  of 
iron,  have  always  been  a  source  of  difficulty  and  trouble  to  pharma- 
cists. This  is  due  to  the  facility  with  which  such  solutions  absorb 
oxygen,  and  become  changed  into  the  ferric  condition,  and  many 
suggestions  of  a  more  or  less  satisfactory  kind  have  from  time  to  time 
been  made  to  obviate  this  objection.  The  plan  now  generally  adopted, 
and  the  one  which  has  been  perhaps  most  successful  is  the  addition  of 
a  small  percentage  of  free  hypophosphorous  acid  ;  even  this,  however, 
is  not  always  found  to  be  satisfactory.  It  is  well  known  that  glycer- 
in possesses  the  property  of  preventing  oxidation  of  ferrous  salts,  and 
even  of  reducing  ferric  salts  to  the  ferrous  state.  Its  sweetness  also 
makes  it  a  convenient  substitute  for  sugar.  From  these  properties  it 
occurred  to  me  that  it  would  be  a  very  suitable  vehicle  for  a  prep- 
aration analogous  to  the  official  syrupus  ferri  iodidi,  and  at  the  same 
time  free  from  the  objections  to  which  the  latter  is  liable.  Some  time 
ago  I  first  prepared  several  such  preparations,  to  which,  following  the 
example  of  the  U.  S.  Pharmacopoeia,  I  have  applied  the  name  glycer- 
itum  or  glycerite,  and  after  a  considerable  experience  they  have  proved 
satisfactory. 
Referring  to  the  literature  on  the  subject,  I  observe  that  the  idea 
has  occurred  to  others  as  well  as  myself.  M.  Veza  (U.  S.  Dispen- 
satory, p.  1796)  gives  a  formula  for  a  20  per  cent.,  and  S.  Plevani  (Year 
Book,  1885,  p.  266),  a  23  per  cent,  solution  of  ferrous  iodide  in  gly- 
cerin.2 These  suggestions  do  not  however  seem  to  have  attracted  gen- 
eral attention,  and  I  have  thought  it  might  be  useful  if  I  were  to 
bring  before  you  some  of  my  experience,  and  one  or  two  working 
formulae.  The  formula  for  glyceritum  ferri  iodidi  from  which  I  have 
been  accustomed  to  work  is  designed  to  yield  a  product  containing  10 
per  cent,  of  ferrous  iodide,  but  adapting  the  proportions  to  the  stand- 
ard of  the  syr.  ferri  iodidi  B.  P.,  the  following  formula  will  be  found 
to  work  well : 
1  Eead  before  the  Pharmaceutical  Society  of  Great  Britain  at  an  Evening 
Meeting  in  Edinburgh,  Tuesday,  April  9;  reprinted  from  Phar.  Jour,  and  Trans., 
April  20,  p.  341. 
2  The  substitution  of  glycerin  for  syrup  was  first  recommended  by  Fr.  Stearns 
(see  Am.  Jour.  Phar.,  1857,  p.  522) ;  and  for  a  portion  of  the  syrup,  by  Dr.  Henry 
Thayer,  in  Amer.  Jour.  Phar.,  1858,  p.  390 —Editor. 
