72 ANAPHYLAXIS AND ANTI-ANAPHYLAXIS 



methods of injection — oral, rectal, subcutaneous,, 

 intraperitoneal, intracerebral, intrathecal, and intra- 

 venous. 



The oral method is the least practical of all, 

 because it requires at least one or two days before 

 anti-anaphylactic immunity is established. 



The rectal method is more prompt in action, but 

 it is subject to some risks, the reabsorption of the 

 antigen by the mucosa being delayed according to 

 individual idiosyncrasy and the nature of the antigen. 



The intraperitoneal and intracerebral methods — 

 above all, the latter — confer immunity in a very short 

 time, varying from a few minutes to an hour at the 

 most. This immunity is the most effective and 

 reliable ; but it is to be understood that these methods 

 may be impracticable in the case of man. 



There remains vaccination by the subcutaneous, 

 intrathecal, and intravenous routes. From these 

 routes the physician will have to make his choice. 



Vaccination by the subcutaneous method, in view 

 of the slow absorption, may be of service in cases in 

 which the injection of therapeutic serum is not 

 urgent . 



According to the sensitiveness of the individual, 

 for the purpose of vaccination, i to 5 c.c. of serum 

 should be injected subcutaneously ; then, four hours 

 later, the whole of the intended dose (20 to 30 c.c). 

 It must, however, be pointed out that there are 

 individuals who are extremely sensitive to subcu- 

 taneous injections ; in those the only route of vaccina- 

 tion is, beyond a doubt, the intravenous path, which 

 will be dealt with farther on. Vaccination by the 

 intrathecal route is above all indicated in cerebro- 

 spinal meningitis, in the course of which disease 

 anaphylactic mishaps are frequent. In order to 

 protect the patient from these, we should begin by 

 introducing into the spinal cavity i or 2 c.c. of serum. 



