760 
Biological  Products. 
Am.  Jour.  Pharm. 
Nov.,  1918. 
the  manufacture  of  diphtheria  antitoxin  and  smallpox  vaccine,  and 
the  general  tendency  is  to  classify  all  bacteriological  products  along 
with  the  two  mentioned.  The  object  of  this  paper  is  to  outline 
briefly  some  information  regarding  other  serums,  vaccines  and  bac- 
terial vaccines,  that  will  be  useful  to  the  retail  druggist  particularly 
if  he  caters  to  business  along  this  line. 
One  often  hears  physicians  and  pharmacists  speak  of  "  those 
vaccines  "  or  "  those  serums,"  including  in  these  terms  the  entire 
list  of  bacteriological  products  that  are  used  in  the  treatment  of 
disease,  and  it  is  not  uncommon  to  hear  the  terms  "  vaccine "  and 
"  serum "  used  interchangeably  without  any  apparent  regard  for 
their  meanings.  It  should  be  borne  in  mind,  therefore,  that  a  serum 
is  a  product  obtained  by  injecting  horses  or  other  domestic  animals 
with  toxins  or  bacteria  in  increasing  amounts  until  the  blood  of  the 
animal  contains  a  sufficient  number  of  antibodies  to  combat  the 
disease  and  then  bleeding  and  separating  the  serum  that  contains  the 
antibodies  from  the  solid  portion  of  the  blood. 
In  this  connection,  we  should  distinguish  between  antitoxic 
serums  and  antibacterial  serums.  The  two  serums  recognized  in 
the  Pharmacopoeia  are  antidiphtheric  serum  and  antitetanic  serum. 
Both  are  antitoxic  serums  and  have  been  popularly  known  as  diph- 
theria antitoxin  and  tetanus  antitoxin.  They  are  prepared  by  inject- 
ing horses,  not  with  the  'bacteria  causing  diphtheria  or  tetanus,  but 
with  the  toxins  generated  by  these  bacteria.  Antistreptococcic  serum 
and  antipneumococcic  serum  are  examples  of  antibacterial  serums, 
because  in  those  cases  the  organisms  causing  the  infections  are  in- 
jected into  horses  in  order  to  produce  the  antibacterial  serums.  In 
the  case  of  tetanus  and  diphtheria,  the  antitoxin  can  be  separated 
from  the  serum  by  precipitation  with  the  proper  chemicals  and  the 
precipitated  antitoxin  is  redissolved  in  physiological  saline  solution 
and  standardized.  In  this  way  a  considerable  quantity  of  antitoxin 
can  be  concentrated  into  a  very  small  bulk.  In  the  case  of  anti- 
bacterial serums,  the  finished  product  is  the  blood  serum  itself. 
The  term  "  vaccine  "  refers  to  a  living  organism  or  virus  used  to 
produce  a  mild  form  of  the  disease  in  that  way  stimulating  the  in- 
oculated person  or  animal  to  produce  anti-bodies  and  thus  ward  off 
infection.  Smallpox  vaccine  and  rabies  vaccine  are  examples  of 
vaccines.  Quite  a  large  group  of  products  spoken  of  as  vaccines  are 
really  not  vaccines  in  the  strict  sense  of  the  term,  because  they  do 
not  represent  living  germs.    Among  bacteriologists,  they  are  known 
