THE  AMEEIC 
JOURNAL  OF  P 
AUGUST,  1Q17 
THE  STABILITY  OF  IODINE  OI 
By  L.  E.  Warren,  Ph.C,  B.S. 
(Contribution  from  the  American  Medical  Association  Chemical 
Laboratory.) 
In  general,  the  literature  on  the  keeping  qualities  of  iodine  oint- 
ment, and  on  the  stability  of  iodine  if  mixed  with  ointment  bases,  is 
confusing.  The  recorded  evidence  is  often  contradictory.  The  at- 
tention of  the  writers  was  brought  to  this  condition  by  studies  of 
several  proprietary  preparations,  Iodex,1  Iod-Izd-Oil,2  Iocamfen,3 
and  Iocamfen3  Ointment. 
Iodex  was  sold  under  the  claim  that  it  is 
"...  an  embodiment  of  vaporized  iodine,  in  an  organic  base,  reduced 
and  standardized  at  5  per  cent,  by  incorporation  with  a  refined  petroleum 
product." 
The  exact  composition  of  Iodex  is  a  trade  secret.  Analysis 
showed  that  it  contains  petrolatum-like  substances  and  combined 
iodine,  the  latter  probably  in  combination  with  oleic  acid.  Tests  for 
free  iodine  were  made  in  five  specimens  of  Iodex.  In  one  of  these 
no  free  iodine  was  present ;  in  the  others  the  merest  traces  were 
found. 
Two  years  ago  a  preparation  called  "Iod-Izd-Oil"  was  ex- 
amined. This  was  claimed  to  contain  2  per  cent,  of  free  iodine  in 
liquid  petrolatum.  At  the  time  of  the  examination  the  age  of  the 
preparation  was  not  known,  but  it  had  been  obtained  just  prior  to 
the  analysis,  and  was  thought  not  to  be  very  old.    The  analysis 
1  Rep.  Lab.  A.  M.  A.,  8,  89  (1915). 
2  Rep.  Lab.  A.  M.  A,  8,  106  (1915). 
z  Rep.  Lab.  A.  M.  A.,  g,  118  (1916). 
