TOXINS AND ANTITOXINS 53 



Therefore, the actual dose employed is to a large extent upon an empiri- 

 cal basis. Park recommends the following table of doses and methods 

 of administration : 



DOSAGE OF UNITS OF ANTITOXIN IN DIPHTHERIA. SINGLE DOSE ONLY. 



Infant, ten to thirty pounds (under two years of age). 



Mild Moderate Severe Malignant 

 2,000 3,OOO 5.OOO 



3,000 5,000 10,000 10,000 



Child, thirty to ninety pounds (under fifteen years of age). 

 3,000 4,000 10,000 10,000 



4,000 10,000 15,000 20,000 



Adults, ninety pounds and over. 



3,000 5,ooo 10,000 15,000 



5,000 10,000 20,000 40,000 



METHOD OF ADMINISTRATION. 



Mild Moderate Severe Malignant 



Subcutaneous or Intramuscular or Intramuscular or y 2 intravenous and 

 intramuscular subcutaneous y 2 intravenous y 2 intramuscular 



and y 2 intramus- or subcutaneous 

 cular or subcu- 

 taneous 



McCombie recommends the following dosages : 

 Mild: 4000 to 8000 units in one dose. 



Moderate: 12,000 to 16,000 units in one dose or two doses. 

 Severe : 20,000 to 50,000 units or more in two or three doses. 

 Laryngeal: 16,000 to 24,000 as initial dose, and repeat once or twice according 

 to persistence of symptoms. 



Improvement following the administration of antitoxin is strik- 

 ing when given early and exhibits itself in fall of temperature, reduc- 

 tion of leucocytosis, reduction of inflammation, and separation of 

 the fibrinous membrane. This improvement varies somewhat with 

 the method of administration, the intravenous method effecting im- 

 provement in somewhat less time than the intramuscular, and the 

 latter in somewhat less time than the subcutaneous. In a series of 

 cases studied in the City Hospital in Cleveland by Ruh the intra- 

 venous form of administration was followed in 83 per cent, of the 

 cases by a severe general reaction with chills and prostration com- 

 ing on a few minutes after the administration and lasting for about 

 twenty minutes. At the present time it is impossible to state the 

 exact cause of this reaction. Such reaction does not follow subcu- 

 taneous and intramuscular injections. It is not due to the preserva- 

 tive, nor as far as can be determined, to the age of the serum. The 

 most reasonable explanation appears to us to be that the reaction is 

 due to foreignness of the horse protein. None of Ruh's cases showed 

 prolonged or fatal reactions, and it is not probable that these reac- 

 tions represent individual hypersusceptibility, because if this were 

 true fatalities would be likely to occur (see page 230). 



Natural Immunity to Diphtheria The Schick Test. It has long 

 been known that many individuals, even as many as 80 per cent, of 

 adults and 50 per cent, of children, are immune to diphtheria, as indi- 



