Am.  Jour.  Ptiarm.  t 
February,  1906.  J 
Nascent  Silver  Iodide. 
65 
intended  to  be  used  as  an  injection  into  the  urethra,  and  the  direct 
object  that  was  sought  to  be  attained  was  to  increase  the  activity  of 
the  silver  salt  and  at  the  same  time  to  eliminate  the  very  objection- 
able tendency  to  stain,  that  is  so  evidently  inherent  to  all  of  the 
soluble  salts  of  silver.  The  assistant  apothecary  duly  called  the 
physician's  attention  to  the  fact  that  the  resulting  mixture  would 
necessarily  contain  something  quite  different  from  what  he  had 
probably  intended,  and  that  in  place  of  using  an  organic  combina- 
tion of  silver  he  would  really  be  using  a  nascent  or  freshly  pre- 
pared silver  iodide  that  could  be  produced  much  more  economically 
by  means  of  silver  nitrate  in  place  of  the  inordinately  expensive 
organic  salt  of  silver.  To  demonstrate  the  accuracy  of  this  state- 
ment, a  corresponding  mixture  was  made  by  using  silver  nitrate  as 
the  source  of  the  silver  iodide. 
This  nascent  silver  iodide  mixture,  prepared  from  silver  nitrate, 
was  subsequently  used  in  a  number  of  cases,  and  was  found  to  be  in 
all  respects  the  equal,  and  in  some  particulars  very  much  superior, 
to  the  mixture  prepared  from  the  proprietary  silver  salt.  The  re- 
sulting preparation,  made  in  the  form  of  an  emulsion,  has  been  used 
quite  freely,  not  alone  at  the  German  Hospital  but  also  in  other 
institutions,  and  a  preliminary  note  on  "The  Use  of  Iodide  of  Silver 
in  Urethritis,"  by  Drs.  Siter  and  Uhle,  was  published  in  the  Univer- 
sity of  Pennsylvania  Medical  Bulletin  for  May,  1905. 
It  may  be  added  here  that  the  use  of  silver  iodide  for  other  pur- 
poses than  that  of  a  local  antiseptic  in  urethritis,  is  not  by  any 
means  of  recent  origin.  Silver  iodide  was  made  official  in  the  U.S. P. 
for  1880,  and,  for  a  period  at  least,  was  extensively  used  for  internal 
administration,  under  the  false  supposition  that,  being  itself  insolu- 
ble, it  would  not  produce  argyria. 
The  popularity  of  silver  iodide  as  an  internal  remedy  was  evanes- 
cent, however,  and  the  preparation  itself  was  omitted  from  the  recent 
eighth  decennial  revision  of  the  Pharmacopoeia. 
From  its  widespread  use  in  photography,  it  has  been  known  for 
a  long  time  that  silver  iodide  exists  in  several  allotropic  forms,  and, 
further,  that  these  allotropic  forms  or  varying  physical  conditions  of 
the  substance  play  a  very  important  part  in  its  chemical  activity 
when  brought  in  contact  with  other  materials.  It  has  also  been 
known  for  a  long  time  that  although  silver  iodide  is  insoluble  in 
water,  it  is  readily  decomposed  by  reducing  agents  into  its  constitu- 
