Name: Dobutamine (Dobutrex)
Class: CHF Rx (Mixed (a-b) Agonist (Cardioselective))
Mechanism: Stim. a and b receptors, but not DA. ® CO w/o HR. stroke volume. No/little change in peripheral resistance. cAMP ® contractility.
Absorption: IV ® rapid onset (1-2 min). Peak effect ~ 10 min.
Dist.:
Metabolism.: Methylation by COMT. Conjugation
Excretion, t½: 2 min.
Toxicity/S.E.s: BP, HR, tachycardia, ventricular ectopic activity. myocard. O2 consump. may cause size MI. Tachyphylaxis to b stim.
Utility: Short-term treatment of cardiac decompensation after cardiac surgery or w/CHF or acute MI. Often DOC after acute MI. Treatment of shock after correction of hypovolemia.