Darifenacin (DFC) is a novel muscarinic M3 selective antagonist used for the once-daily oral treatment of urinary incontinence and overactive bladder. Molecular modelling analyses based on molecular mechanics, semi-empirical (PM3) and DFT (at B3LYP/6-31G* level) calculations show that DFC and its metabolites have large LUMO-HOMO energy differences ranging from 5.2 to 5.6 eV, indicating that DFC and all its metabolites would be kinetically inert. The molecular surfaces of DFC and its metabolites are found to abound in neutral (green) and electron-rich (red and yellow) regions so that the compounds may be subject to lyophilic and electrophilic attacks. None of the compounds abounds in electron-deficient (blue) regions so that none may experience any significant nucleophilic attacks such as those due to glutathione and nucleobases in DNA. This means that DFC and its metabolites may not induce cellular toxicity that results from glutathione depletion and may not cause DNA damage that results from oxidation of nucleobases.