dobutamine (Dobutrex)

Introduction

Tradename: Dobutrex. Dobutamine hydrochloride.

Indications

• refractory acute heart failure, cardiogenic shock
• dobutamine stress echocardiography

Dosage

250 mg in 250 mL D5W (1 mg/mL) @ 2-20 ug/kg/min

• max: 40 ug/kg/min
• 70 kg: 21 mL/hr = 5 ug/kg/min.

Titrate to:

• hemodynamic effect
• excessive tachycardia
• arrhythmia

Stability:

• remix every 24 hours
• keep acidic, incompatible with sodium bicarbonate

Pharmacokinetics

• onset of action is < 2 min
• metabolized primarily by the liver
• eliminated in the urine
• 1/2life is approximately 3 minutes

elimination via plasma

1/2life = 3 minutes

Adverse effects

• common (> 10%)
  • ectopic heartbeats
  • increased heart rate
  • elevation in blood pressure
• less common (1-10%)
  • premature ventricular beats, chest pain, angina, palpitations, dyspnea, headache, nausea/vomiting, paresthesias, mild leg cramps
• may occasionally induce atrial fibrillation
• contains sulfite (asthmatics may be sensitive)

• drug adverse effects of adrenergic receptor agonists
• drug adverse effects of beta-adrenergic receptor agonists
• drug adverse effects of sympathomimetic(s)

Drug interactions

• beta-blockers antagonize effects of dobutamine
• tricyclic anti-depressants (TCA) may potentiate the pressor effects of dobutamine

• drug interaction(s) of beta-2 adrenergic receptor agonists with beta adrenergic receptor antagonists
• drug interaction(s) of beta-2 adrenergic receptor agonists with loop diuretics
• drug interaction(s) of beta-2 adrenergic receptor agonists with thiazide diuretics

Mechanism of action

• stimulates beta-1 adrenergic receptors
• mild beta-2 adrenergic agonist & alpha adrenergic agonist effects
  • ref claims beta-1 adrenergic agonist & beta-2 adrenergic agonist effects without mention of alpha adrenergic agonist effect
• unlike dopamine, does not cause release of stored norepinephrine
• does not effect dopamine receptors
• hemodynamic effects
  • inotropic stimulation
  • reflex arterial vasodilation
  • afterload reduction
  • increased cardiac output
  • blood pressure generally unchanged
  • heart rate may increase in response to decreased left ventricular filling pressure
  • dobutamine does not significantly increase myocardial oxygen demand in the absence of tachycardia

More general terms

• beta-1 adrenergic receptor agonist
• inhaled beta-2 adrenergic receptor agonist
• vasoconstrictor agent or vasopressor
• inotropic agent

Additional terms

• dobutamine stress echocardiography

Database

• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=36811
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=3141
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=65324
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=208850
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=3038222