Epinephrine activates all adrenergic receptors: α1, α2,β1, β2, and β3
Bolus dose
The usual bolus doses for pressure support begin at 2 to 8 μg given intravenously
0.02 mg/kg or approximately 1.0 mg : given for cardiovascular collapse, asystole, ventricular fibrillation, electromechanical dissociation, or anaphylactic shock
In pediatric patients, current recommendation is an initial dose of 0.01 mg/kg repeated every 3 to 5 minutes throughout resuscitative attempts
Infusion
A rate of 1 to 2 μg/minute, although rarely used, should predominantly activate β2 receptors, with resulting vascular and bronchial smooth muscle relaxation.
A rate of 2 to 10 μg/minute (25 to 120 ng/kg/minute) increases heart rate, contractility, and conduction through the AV node and decreases the refractory period.
Doses in excess of 10 μg/minute (100 ng/kg/minute) cause marked α-adrenergic stimulation with resultant generalized vasoconstriction