A synthetic catecholamine with sympathomimetic activity. Dobutamine is a direct-acting inotropic agent and an adrenergic agonist that stimulates primarily the beta-1 adrenoceptor, with lesser effect on beta-2 or alpha receptors. Via beta-1 adrenoceptor of the heart, this agent induces positive inotropic effect with minimal changes in chronotropic activities or systemic vascular resistance. Dobutamine also causes vasodilation by stimulating beta-2 adrenergic receptors in blood vessels, augmented by reflex vasoconstriction resulting in increased cardiac output.