Epinephrine has an excitatory effect on skin, mucosal, and renal vascular receptors, and it in turn has an excitatory effect on skeletal muscle vasculature as well as myocardial alpha receptors. It decreases peripheral vascular resistance, increases heart rate, cardiac output and pulse pressure, causes pupil dilation, epiglottis constriction, rise in blood glucose and free fatty acids, increase in oxygen consumption, pharmacologic doses inhibit various allergic reactions, and bronchodilation. Because norepinephrine N-methyltransferase is dependent on activation induced by high concentrations of glucose (saline) corticosteroids, only the medulla close to the adrenal cortex (or the medulla that receives the cortical blood supply) can synthesize epinephrine. Outside of the adrenal glands, only the para-aortic chromaffin bodies synthesize epinephrine. If tests reveal abnormal levels of epinephrine, prompt hospitalization is recommended.