Low Catheterization Rates After Botox for OAB

Intravesical onabotulinumtoxinA (Botox®) is a treatment for overactive bladder (OAB), but a known concern is post-procedure urinary retention that may require clean intermittent catheterization (CIC). Many providers ask patients to demonstrate willingness to self-catheterize before choosing this treatment. However, urinary retention doesn’t always necessitate CIC, especially in asymptomatic patients.

This study analyzed the true need for catheterization after Botox injections in a tertiary pelvic medicine practice. Over the study period, 187 Botox injections were administered using 100 units of onabotulinumtoxinA into the detrusor muscle, including the trigone. Follow-up occurred two weeks post-procedure using bladder ultrasound to check post-void residual (PVR) urine volume. Retention was defined as symptomatic incomplete emptying with a PVR ≥350 ml.

Findings revealed that only 3 patients (1.6%) needed CIC. Among the 13 patients with a PVR ≥350 ml, 12 were asymptomatic and managed conservatively—none developed acute urinary retention, and their PVR normalized within about 6 weeks. An additional 29 patients had a PVR between 200–350 ml but were also asymptomatic and did not require CIC. The remaining 143 patients had PVRs under 200 ml.

This data suggests that while elevated PVR is common, actual symptomatic retention requiring catheterization is rare. By using less rigid criteria for initiating CIC, the study demonstrates a significantly lower catheterization rate than previous clinical trials. These results can reassure patients considering Botox for OAB that the risk of needing catheterization is minimal, especially if they remain symptom-free. Careful follow-up is still essential.

Favre, N., & Gill‑Burke, D. (2017, August 22). What is the true catheterization rate after intravesical onabotulinumtoxinA injection: Beyond the abstract. UroToday: Recent Abstracts, Pelvic Health & Reconstruction — Overactive Bladder. Retrieved from https://www.urotoday.com/recent-abstracts/pelvic-health-reconstruction/overactive-bladder/98069-what-is-the-true-catheterization-rate-after-intravesical-onabotulinumtoxina-injection-beyond-the-abstract.html