260 CORTEX 



avoids deceiving oneself by results based on an incomplete 

 operation. 



THE SUPERIORITY OF ORAL OVER PARENTERAL ADMINISTRATION 

 OF THE CORTICAL HORMONE 



The parenteral administration of any therapeutic agent 

 suffers from the disadvantage that it necessitates the prepara- 

 tion of a highly purified product. The presence of toxic im- 

 purities may easily mask the beneficial effects of any hormone 

 present in a given extract. Thus, in an experiment in which 

 an incompletely purified extract was administered intraperi- 

 toneally to adrenalectomized rats, doses of one cubic centimeter 

 per rat per day failed to provide complete replacement therapy. 

 The same extract administered orally by mixing with the 

 animals' food served as a complete replacement therapy in 

 doses as small as 0.05 cubic centimeters. The noxious impuri- 

 ties present in this extract were without deleterious effects 

 when administered orally. 



Another important advantage favoring oral therapy in 

 administering the adrenal cortical hormone is the fact that this 

 hormone is much more effective when administered in multiple 

 doses than when an equal amount is administered in a single 

 dose. This advantage of divided doses at frequent intervals 

 is attained practically only with an oral method of therapy. 



The early work on the relative efficacy of oral as compared to 

 parenteral administration of the cortical hormone indicated 

 that it required about five times as great a dose for oral use as 

 for intraperitoneal injection. 246 This apparent superiority of 

 the parenteral mode of administration was based on a compari- 

 son of the effects of a single dose administered by stomach tube 

 with the effects of a single injection. However, if one compares 

 the effects of a single parenteral injection with the results which 

 follow the administration of the hormone in the animals' food, 

 one finds that the oral method of administration yields better 

 therapeutic results than the parenteral administration of the 



