Am.  Jour.  Pharm. ) 
May,  1921.  ) 
The  Quinotoxin  Myth. 
341 
raises  the  blood  pressure  slightly.  Biberf eld  7  found  this  toxicity  for 
mammals  quite  low  (lethal  dose,  15  mg.  per  kilogram  by  vein;  200 
mg.  hypodermically,  corresponding  to  about  ounce  in  man).  In 
this  large  dose,  it  produced  convulsions.  It  did  not  have  a  digitexin 
effect  on  the  exposed  frog  heart,  but  depressed  it  like  quinin.  It 
also  depressed  other  smooth  muscle;  it  produced  local  anesthesia 
similar  to  quinin,  but  was  not  antipyretic. 
Actions  of  Cinchonicin. — The  toxity  of  this  is  also  low.  Hilde- 
brandt  found  the  hypodermic  lethal  dose  as  150  mg.  per  kilogram 
for  mice?  (equivalent  to  10  gm.  for  a  man).  The  same  dose  of  cin- 
chonin  was  not  toxic.  Hunt 8  obtained  about  the  same  number  for 
cinchotoxin  (310  mg.)  as  for  quinin  (370  mg.).  Rabbits  seem 
considerably  more  susceptible.  Biberfeld,  minimum  fatal  dose, 
hvpodermically,  10  mg.  per  kilogram ;  Fraenkel,  fatal  dose,  hypoder- 
mically, 20  mg.  per  kilogram;  Hildebrandt,  cat,  fatal  dose,  hypo- 
dermically, 20  mg.  per  kilogram.  Death  is  preceded  by  violent  con- 
vulsions. 1 
Hildebrandt  described  a  slight  rise  of  blood  pressure.  Biber- 
feld found  depression  of  the  circulation.  Fraenkel.  in  the  exposed 
heart,  observed  first  very  strong  contractions,  then  diastolic  arrest. 
conclusions. 
There  is  no  occasion  to  fear  toxic  effects  from  the  transforma- 
tion of  quinin  into  "quinotoxin"  (more  properly,  quinicin).  This  sub- 
stance is  not  especially  toxic,  and  it  could  not  be  formed  in  signifi- 
cant quantities,  if  at  all,  in  the  body. 
It  may  be  formed  in  prescriptions  containing  quinine  and 
organic  acids ;  but  this  would  proceed  very  slowly,  and  the  quinicin 
would  undergo  further  transformation  into  inactive  products.  Such 
solutions  are  perfectly  proper  if  used  within  a  few  days.  They 
should  not  be  used  after  prolonged  standing,  when  they  become  dis- 
colored and  precipitated;  not  because  they  have  become  toxic,  but 
because  they  have  become  inactive. 
7  Biberfeld,  J.:  Arch.  f.  exper.  Path.  u.  Pharmakol.  79:361,  1916. 
8  Hunt,  Reid :  Arch,  internat.  de  pharmacod.  12 :  500,  1903. 
