PHARMACOLOGY OF EPINEPHRINE 137 



tives of epinephrine are extremely toxic and in large doses 

 may prove harmful even when administered orally. Severe 

 gastric and intestinal cramps are the commonest symptoms 

 following the oral administration of epinephrine. Doses of 4 

 cc. of a one per cent solution have been advocated 83 for the 

 oral treatment of several conditions but in view of what we 

 have stated above, the oral use of epinephrine must be dep- 

 recated. 



That some epinephrine is absorbed after oral administra- 

 tion is manifested by the hyperglycemia resulting from the 

 administration of 4 milligrams of epinephrine to man 83 and 

 by the effects of an oral dose on the iris of the cat, after removal 

 of the superior cervical ganglion. The epinephrine which is 

 absorbed from the gastro-intestinal tract is carried first to the 

 liver where it exerts its glycogenolytic action and is destroyed 

 before it can exert any cardio-vascular effect. Rectal adminis- 

 tration which results in absorption into the general circula- 

 tion before reaching the liver is more effective than oral ad- 

 ministration. 



The pharmacological effects of epinephrine are rapidly elici- 

 ted after injection but very transient if directly introduced into 

 the blood stream. 661 When injected subcutaneously, epineph- 

 rine is absorbed along the lymph channels. The local vaso- 

 constriction occurring at the point of injection retards the 

 rate of absorption of the epinephrine and thus prolongs its 

 action. The subcutaneous route of administration is always 

 preferable except in emergency treatments where the circula- 

 tion is too much retarded or the heart has stopped, in which 

 cases intravenous and intracardiac injections, respectively, are 

 required. 328 



As an analeptic, in cases where the heart has stopped, as in 

 shock, anesthesia, electrocution, drowning, suffocation, et cet- 

 era, epinephrine must be injected intracardially to produce the 

 desired effect. An injection into the heart muscle is much 

 more effective than an injection into the cardiac cavity, for 



