Botulinum toxin A injection in the external urethral sphincter: A narrative review of applications in detrusor underactivity and sphincteric disorders

Detrusor underactivity (DUA) significantly impacts the quality of life in patients and is often associated with nonspecific symptoms, including both voiding and storage issues. Current treatment options, such as behavioral modifications, pharmacologic therapy, and sacral neuromodulation, are commonly employed but often result in unsatisfactory outcomes. Botulinum toxin A, known for its ability to temporarily paralyze muscles, is widely used in fields like the treatment of gastroparesis, dysphagia, and anal obstruction, and in cosmetic procedures. This property positions it as a potential option for reducing bladder outlet resistance, potentially improving voiding function in patients with DUA. In this review, we examine the application of botulinum toxin A in the management of DUA and discuss its use in sphincteric injections for other sphincter dysfunction conditions. We provide a comprehensive, up-to-date review of the use of sphincteric injections of botulinum toxin in addressing DUA and other sphincter dysfunctions.