Possible therapeutic effect on nocturia after radical prostatectomy by OnabotulinumtoxinA injection: a case series

Abstract Background Intravesical onabotulinumtoxinA (BTX-A) injection is an established treatment for overactive bladder (OAB) in patients who do not respond to conventional medical therapy. This study aimed to evaluate the safety and efficacy of BTX-A injections in patients with urinary dysfunction after radical prostatectomy (RP). Methods This retrospective case series included 11 post-RP patients with urinary dysfunction who received intravesical BTX-A injections and were followed-up for 12 months. We measured and analyzed the efficacy of BTX-A treatment using the Overactive Bladder Symptom Score (OABSS), International Prostate Symptom Score (IPSS), quality of life score, and number of pad sheets used before and after intravesical BTX-A injection. Results Following BTX-A injections, significant improvements were observed in the OABSS Q2 score, which evaluates nocturia. The median (IQR) OABSS Q2 score improved from 3.0 (2.0–3.0) at baseline to 1.0 (1.0–2.0, p = 0.012) at 3 months. Similarly, the IPSS Q7 score showed notable changes. The baseline median (IQR) was 3.0 (2.0–4.0), which significantly reduced to 2.0 (2.0–2.5, p = 0.036) at 1 month. Further improvement was observed at 3 months, with a median (IQR) of 2.0 (1.0–2.5, p = 0.021). There were no statistically significant differences in the other categories. There were no statistically significant differences among the other categories. Conclusion Intravesical BTX-A injections significantly improved nocturia without complications in post-RP patients. This treatment represents a potential therapeutic option for managing refractory nocturia after RP.