CHAPTER XXXII 

 CHEMOTHERAPY 



FROM the earliest times, healers of the sick have sought specific 

 remedies in the form of drugs or methods that would always and un- 

 failingly effect the cure of a certain disease, and indeed this search has 

 been extended for a single remedy that will cure all diseases, regardless 

 of their origin and nature. To this end, throughout the ages experimen- 

 tation, conscious or otherwise, has gone hand in hand with medicine. 

 Countless substances gathered from the vegetable, animal, and mineral 

 kingdoms have been experimented with, but for the most part have been 

 discarded. Despite this persistent search for specifics, until compara- 

 tively recent times but two remedies have been found worthy of being 

 regarded as specifics, namely, cinchona bark for malaria, a remedy dis- 

 covered by the South American Indians, and mercury for syphilis. 



With discoveries in bacteriology and the establishment of the etio- 

 logic relationship of various microorganisms to certain diseases, test- 

 tube experiments soon demonstrated that certain substances could 

 quickly and easily destroy these microparasites. It was apparent, how- 

 ever, that in the animal body conditions were different ; here the germi- 

 cide, even when administered in doses sufficiently large to prove dangerous 

 to life, usually failed to kill the microorganisms. The exceptions were 

 quinin and mercury, which we now know are specifically germicidal for 

 the plasmodium and spirochete respectively, a fact that was suspected 

 long before the parasites themselves were discovered. 



In the latter part of the eighties it was discovered that ,the blood 

 possessed germicidal powers, and rapid advances were soon made in our 

 knowledge of the defensive mechanism of the animal body, and the 

 means afforded for preventing infection, and even of successfully over- 

 coming it if, by any chance, microorganisms passed the normal barriers 

 and gained a foothold on the tissues proper. Here indeed was a more 

 or less specific therapy that was not suspected until 1894, when diph- 

 theria antitoxin was discovered. It was then speedily realized that 

 body-cells could be made to produce a specific remedy for a certain dis- 

 ease, and it was naturally assumed that this was possible for all those 



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