To discuss the pharmacotherapeutic aspects of Mirabegron which is a first-in class novel β3 receptor agonist drug recently approved by the food and drug administration (FDA) for the treatment of overactive bladder (OAB).We conducted a computerized search of the MEDLINE/PUBMED databases with the word Mirabegron, β3 receptor agonist and overactive bladder.Effect of Mirabegron on β3 adrenergic receptor purportedly releases nitric oxide(NO) by an increase in intracellular Ca2+ through accumulation of cyclic adenosine monophosphate (cAMP).