The results for a positive response on the treatment benefit scale of “greatly improved” or “improved” were also highly significant, in that 62.8% of patients receiving onabotulinumtoxinA reported a positive response in comparison to 26.8% of patients receiving placebo ( P <0.001).
The rate of Acute urinary retention showed a trend toward the greatest incidence in the frail elderly. 46 In another study of 21 patients aged >75 there were no cases of elevated PVR or urinary retention. 28 The incidence of retention at higher doses prompted the FDA to approve the 100 U dose for non-neurogenic OAB, and this is the recommended dose to maximize efficacy while minimizing side effects.