200 EPINEPHRIN. 



EPINEPHRIN. 



Epinephrin, or "adrenalin" (CoHisNOs == 181.76) is an active principle derived 

 from the suprarenal glands of the ox and the sheep. 



Pharmacodynamics. 



Central Nervous System. Epinephrin stimulates the terminals of nerve fibers 

 from the thoracicolumbar cord. 



Muscular System. No action. 



Respiration. No action; but relaxes bronchial muscle. 



Heart is first accelerated from stimulation of the accelerator terminals; then 

 slowed reflexly from centric vagus action ; then quickened as vagus control is inhibited 

 or overcome. 



Blood-pressure shows an extraordinary, though transient, rise, due to stimula- 

 tion of the myoneural junctions of those constrictor fibers supplied from the thoracico- 

 lumbar cord. 



Eye. Pupil is dilated through stimulation of the dilator fibers. 



Alimentary Tract. Stimulation of the splanchnic terminations is said to cause 

 peristaltic inhibition and intestinal relaxation, and contraction of the pyloric, ileocolic 

 and anal sphincters ; increased movements of the gall-duct. 



Secretory glands are slightly stimulated. Increased glycogenolysis. Urine ar- 

 rested then augmented; local. 



Metabolism. No apparent change. 



Temperature. Not affected. 



Absorption does not take place readily from the mucosa. It is absorbed slowly 

 from the subcutaneous tissues, but more readily from the muscular tissues. Its action 

 is very rapid intravenously. 



Excretion. Epinephrin is rendered inert very promptly by some counteracting 

 substance in the blood or vessel walls. 



Local Action. Epinephrin induces a prompt ischsemia through local vasocon- 

 striction. 



Symptoms. 



Therapeutic Doses. Toxic Doses. 



Cerebral congestion. Glycosuria. 



Acceleration of the heart, followed Diuresis. 



by strong, full beat. Inflammations of liver and kid- 



Remarkable, though fleeting, rise ney. 



of blood-pressure. Prostration. 



Collapse of central nervous sys- 



tem. 



Respiratory failure. 

 Pulmonary edema. 

 Therapeutics. 



Epinephrin may be employed to produce local ischsemia, to arrest hemorrhage 

 from mucous surfaces ; and, if used intravenously, to combat shock ; it is also used in 

 asthma to relax bronchial spasm. 



Dosage. 



Epinephrin in i : 1000 solution. 



For local application, use full strength. 



For hypodermic use, dilute one-half with normal salt solution. 



For intravenous use, dilute I to 10 with Locke's solution. 



