<prompt> M3 Receptor antagonist used in the treatment of bladder over activity is:TamsulosinDesmopressinDoxazosinDarifenacin  <response>: Ans: d Darifenacin Ref:Campbells urology, 9th ed,p. 2093Darifenacin is a relatively selective M muscarinic receptor antagonist used in bladder overactivity.The other anti muscarinic agents used are:TolterodineTrospiumSolifenacinPropanthelineAtropineHyocyanine 