Botulinum toxin injections for overactive bladder

This study determined the safety and effectiveness of onabotulinumtoxinA (BOTOX1) compared to a placebo in adults with overactive bladder. The study concluded that botulinum toxin led to greater reductions in symptoms, but also significant side effects.

Overactive bladder (OAB) syndrome is a condition characterized by a sudden, uncontrollable urge to urinate (void). Leaking urine (incontinence) and many trips to the bathroom during the day and night are common symptoms of OAB.

Medications which relax the bladder are commonly prescribed to treat OAB symptoms. However, their benefit is limited, and long-term use is associated with significant side effects.

OnabotulinumtoxinA (BOTOX1) injection into the bladder muscle is an effective option for patients with OAB who do not respond to, or cannot tolerate, oral medications. Botulinum toxin relaxes the bladder muscle, reducing the urge to urinate.

This study analyzed results from seven different trials to determine the safety and effectiveness of botulinum toxin injections. A total of 1770 patients with OAB were given either onabotulinumtoxinA injection, or a placebo (a substance with no active effect) injection.

Patients given treatment reported significant improvements in frequency of urination, urgency of urination, incontinence, and nighttime urination. Overall, botulinum toxin treatment was noted as very effective compared to placebo.

However, botulinum toxin treatment was also associated with side effects. On average, 30.1% of patients experienced urinary tract infections (compared to only 10.8% of patients receiving placebo). Urinary tract infections were also more severe in the treatment group.

11.2% of patients receiving botulinum toxin, and 7.8% of those receiving a placebo, experienced dysuria (painful urination).

Treatment with botulinum toxin was also associated with urine retention (inability to pass urine), reported in 11.8% of patients receiving treatment (compared to 0.5% among placebo patients).

This study concluded that onabotulinumtoxinA injections are effective at reducing OAB symptoms, but are associated with significant side effects.