To determine if intradetrusor injection of onabotulinumtoxin-A (BTX-A) would reduce postoperative narcotic and anticholinergic requirements in children undergoing open continent bladder reconstruction. After institutional review board approval, we retrospectively reviewed all bladder reconstructions performed. Bladder reconstruction was defined as the following procedures in any combination: bladder neck reconstruction and sling, bladder neck closure, Mitrofanoff, Monti, or bladder augmentation. We identified 15 children who underwent reconstruction with BTX-A injection and compared these with 15 children who did not receive BTX-A. Postoperative narcotic and anticholinergic requirements were recorded as well as length of stay, time to diet, time to return of bowel function, and complications. All medications were converted to morphine mEq/kg per day or mg/kg per day to standardize for patient size and length of stay. Thirty patients who underwent open bladder reconstruction were included. Fifteen received BTX-A injection and 15 did not. The BTX-A group required significantly less narcotic medication postoperatively compared with the no-BTX-A group (0.32 vs 0.85 morphine mEq/kg per day; P = .0002). The BTX-A group also required significantly less anticholinergic medication compared with the no-BTX-A group (0.22 vs 0.88 mg/kg per day; P = .024). There was no significant difference between the groups with respect to length of stay (98.27 vs 9.287 days; P = .34) or return of bowel function (5.53 vs 4.93 days; P = .994). Complication rate between the groups was similar (P >.99). Intraoperative injection of BTX-A significantly reduced postoperative narcotic and anticholinergic requirements in patients who underwent open continent bladder reconstruction. This is an encouraging alternative treatment to manage postoperative pain with no associated risk of significant complications.