^March,^™'}  /        Syrup  of  Hydr iodic  Acid.  121 
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SYRUP  OF  HYDRIODIC  ACID. 
By  F.  W.  Haussmann. 
Research  Committee  B.,  Pharmacopoeia  Revision. 
Few  official  preparations  have  been  subjected  to  as  much  adverse 
criticism  as  this  syrup. 
The  objections  are  based  chiefly  on  chemical  grounds,  and  sug- 
gestions to  omit  it  from  the  Pharmacopoeia  or  to  recommend  recent 
preparations  from  a  solution  of  hydriodic  acid  have  frequently  been 
published  in  various  journals. 
In  view  of  the  popularity  enjoyed  in  many  localities,  acquiescence 
to  such  demands  would  be  ill-timed  and  unjust,  and  the  policy  of 
condemning  a  preparation  because  changes  take  place  which  with 
due  precaution  may  in  a  measure  be  prevented,  or,  after  taking 
place,  remedied  with  but  little  difficulty  or  cost,  with  no  impair- 
ment of  appearance  or  diminution  in  strength,  would  prove  only 
beneficial  to  manufacturers. 
A  result  of  its  omission  from  the  Pharmacopoeia  would  be  the 
liability  of  physicians  to  specify  private  makes.  Under  the  pre- 
tence of  superior  stability  such  preparations  would  displace  the 
official  article,  while  such  claims  are  in  no  manner  either  substan- 
tiated or  justified. 
Syrup  of  hydriodic  acid,  prepared  according  to  official  directions, 
is  equal  to  any  similar  preparation  in  the  market,  may  be  confi- 
dently recommended  as  such,  and  the  material  decrease  in  cost  by 
self- manufacture  should  induce  every  pharmacist  to  prepare  his  own 
syrup. 
PREPARATION. 
The  Pharmacopoeia  directs  the  hydriodic  acid  for  the  syrup  to  be 
prepared  by  double  decomposition  between  potassium  iodide  and 
tartaric  acid,  preventing  the  liberation  of  free  iodine  by  the  addition 
of  potassium  hypophosphite. 
Diluted  alcohol  is  employed  to  prevent  solution  of  the  precipi- 
tated potassium  bitartrate. 
The  writer  has  no  substitute  to  offer  in  preference  to  this 
method. 
The  formula  of  the  Pharmacopoeia  of  1880,  which  directed  the 
acid  to  be  prepared  by  the  action  of  hydrogen  sulphide  upon  an 
alcoholic  solution  of  iodine,  was  deservedly  unpopular,  and  the  pre- 
