Dobutamine

Indications

• heart failure

• cardiogenic shock

• indicated when parenteral therapy is necessary for inotropic support in the short-term treatment of patients with cardiac decompensation due to depressed contractility, which could be the result of either organic heart disease or cardiac surgical procedures.

• Not useful in ischemic heart disease because it increases heart rate and thus increases myocardial oxygen demand.

Administration/Absorption

• • IV infusion

Distribution

Dosage

Mechanism

• Direct-acting inotropic agent whose primary activity results from stimulation of the beta-adrenoceptors of the heart

  • Produces comparatively mild chronotropic, hypertensive, arrhythmogenic, and vasodilative effects

  • Does not cause the release of endogenous norepinephrine, as does dopamine

  • Primary activity results from stimulation of the β₁-adrenoceptors of the heart, increasing contractility and cardiac output.

  • Since it does not act on dopamine receptors to induce the release of norepinephrine (another α₁ agonist), dobutamine is less prone to induce hypertension than is dopamine.

  • Predominantly a β₁-adrenergic agonist, with weak β₂ activity, and α₁ selective activity

    • used clinically in cases of cardiogenic shock for its β₁ inotropic effect in increasing heart contractility and cardiac output.

  • Administered as a racemic mixture consisting of both (+) and (−) isomers

    • the (+) isomer is a potent β₁ agonist and α₁ antagonist

    • the (−) isomer is an α₁agonist.^[4]

    • (+)-Dobutamine also has mild β₂ agonist activity, which makes it useful as a vasodilator.^[5

Excretion

• • Half life 2 minutes

  • In human urine, the major excretion products are the conjugates of dobutamine and 3-O-methyl dobutamine

Side effects

• • Increased risk of arrhythmia, including fatal arrhythmias

  • Hypertension, angina, arrhythmia, and tachycardia

  • Used with caution in atrial fibrillation as it has the effect of increasing the atriovenrticular (AV) conduction

Interactions

Contraindications