Inotropes

Dobutamine

• Predominantly β1-adrenergic agonist (weak β2 and α1 activity)
• Increases heart contractility and cardiac output
• Less likely to cause hypertension than Dopamine as doesn't stimulate noradrenalin production

Dopamine

• Causes increase in sodium excretion by the kidneys, an increase in urine output, an increase in heart rate, and an increase in blood pressure
• Stimulates several dopamine receptors (which in turn increase noradrenalin)
• Cardiovascular effects primarily result of dopamine acting at α1, β1, and β2 adrenergic receptors