<prompt> Atenolol is predominantly excreted by -Hepatic metabolismRenal excretionBoth hepatic and renal excretionNon enzymatic elimination  <response>: Ans. is b i.e., Renal excretion Remember Nodalol is longest acting b-blocker Esmolol is shortest acting b-blocker Acebutolol possesses all activities i.e., cardioselectivity, partial agonist activity, membrane stablizing activity and lipid insolubility. Beta blockers approved for treatment of CHF: Carvedilol most widely used, metaprolol, bisoprolol. Carvedilol is a b1 b2 a1 adrenoreceptor blocker with a : b blocking property of 1 : 9. It produces peripheral vasodilatation due to a-1 blockade as well as calcium channel blockade direct effect. It also has antioxidant and antimitotic properties. Atenolol, sotalol and nodalol are primarily excreted by kidney - should not be given in renal failure. Sotalol, penbutolol and pindolol have almost 100 bioavailibility. Penbutolol has maximum oral absorption. Carvedilol has maximum plasma protein binding. Celiprolol has minimum plasma protein binding. Butoxamine is a selective b2 blocker. 