Intradetrusor Botulinum Toxin A at Doses of 100 and 200 Units for Urinary Incontinence in Women: A Single-Center Retrospective Study From Saudi Arabia

Background: Intradetrusor botulinum toxin type A (BoNT-A) is an effective treatment for refractory urgency urinary incontinence (UUI), but real-world data from the Middle East are limited, and clinical practice varies between 100-unit and 200-unit doses.This case series describes outcomes and safety of intradetrusor BoNT-A, by dose administered, in women with UI at a Saudi tertiary center.Methods: The study population comprised female patients diagnosed with UI, including urge, mixed, and idiopathic overactive bladder (OAB)-related incontinence, who had received at least one intravesical BoNT-A injection during the defined study period at King Abdulaziz University Hospital (KAUH).The primary outcome was documented clinical improvement in incontinence.Secondary outcomes were time to improvement, percentage reduction in incontinence episodes, retreatment, patient satisfaction, and adverse events.Analysis was descriptive because of the small cohort and unequal dose groups.Results: Ten female patients were identified, and one, with multiple sclerosis, was excluded; nine (mean age 68.7 ± 8.9 years) were included.Seven (78%) received 100 units, and two (22%) received 200 units of BoNT-A administered under cystoscopic guidance.Clinical improvement was documented in 3/9 (33%) patients (2/7 at 100 units; 1/2 at 200 units), while the other six (67%) had no meaningful response.Responders had 70% to 95% reductions in incontinence episodes, beginning at six to 24 weeks (median eight weeks) and lasting about four months to two years.Mean reduction across the cohort was 28.3%.Seven patients (n=7, 78%) were recorded as needing further treatment: six (67%) non-responders and one (11%) responder whose effect lasted about four months and was reinjected, the only repeat injection in the series.Three patients (33%), all in the 100-unit group, developed transient urinary retention with urinary tract infection (UTI) and dysuria; none needed catheterization.Satisfaction followed response: 2/3 (22%) responders were satisfied, one (11%) was neutral, and six (67%) non-responders were dissatisfied.Conclusions: In this small case series, intradetrusor BoNT-A had an acceptable short-term safety profile.The response was all-or-nothing: three of nine women improved substantially, and six did not, and no doserelated difference could be assessed given the numbers.These descriptive findings are hypothesisgenerating and support larger prospective multicenter studies to optimize BoNT-A dosing protocols in diverse populations, particularly within Middle Eastern healthcare contexts.