Pharmacology 



PHARMACOLOGY is a science inclusive of all 

 exact knowledge of the action of substances 

 and physical conditions upon the animal body. 

 Therapeutics is an art employing, among other 

 things, knowledge pharmacologically derived. 



Experiments made upon man laid the founda- 

 tions of pharmacology, but the limitations of such 

 experimentation made progress slow. Experiments 

 upon animals permit of fixed conditions and scientific 

 controls. Such precise conditions lead to precise 

 determinations of toxic and physiological actions, 

 which are a useful guide in, first, determining if a 

 drug possesses activity; second, ascertaining what 

 that activity is; third, analyzing and explaining the 

 determined action; and fourth, suggesting its possible 

 range of therapeutical usefulness. 



Pharmacology is a somewhat iconoclastic science. 

 For instance, it proved that strychnine has no direct 

 action on the heart, and that opium has no local 

 action in depressing sensory nerve-endings. Thus 

 doubt has been thrown upon many old therapeutic 

 teachings. On the other hand, much new therapy 

 has resulted, largely owing to pharmacology ex- 

 plaining many things. For instance, citric acid 

 removes the calcium ions from the blood and is 

 excreted in the urine as a carbonate. Hence we 

 use oranges to alkalinize the urine. The hypnotics 

 and narcotics have a selective affinity for the cen- 



49 



