Activates all four adrenergic receptor subtypes.

Activation of alpha-1 receptors causes vasoconstriction making epinephrine suitable for: controlling superficial bleeding, delaying absorption of local anesthetics, reducing nasal congestion and elevating blood pressure.  Alpha-1 receptors located on the iris cause mydriasis when activated, which is useful for ophthalmologic procedures.

Activation of beta-1 receptors on heart causes increase in heart rate, increased force of contraction and increases AV conduction velocity.  Therapeutically then, epinephrine can be used to overcome AV heart block and restore cardiac function in patient with cardiac arrest.

Activation of bets-2 receptors in lungs causes bronchodilation in patients with asthma.

Epinephrine used to treat anaphylactic shock.

Can cause hypertensive crisis, dysrhythmias, angina pectoris, necrosis of IV site, and hyperglycemia in diabetics.

MAOIs will prolong and intensify effects, as will tricyclic antidepressants.  Use with general anesthetics can result in dysrhythmias.  Alpha blockers and beta blockers can prevent epinephrine from activating receptors.

Use with caution in patients with hyperthyroidism, cardiac dysrhythmias, hypertension, diabetes, angina pectoris and in patients taking MAOIs, tricyclic antidepressents or general anesthetics.  Monitor cardiovascular status during use, and monitor blood glucose in diabetic patients.  Assess IV site for necrosis.