Adverse Events Common After Botulinum Toxin Injections
WASHINGTON, D.C.—Adverse events (AEs) after intravesical botulinum toxin type A for idiopathic detrusor overactivity (IDO) are encountered frequently, according to a new study presented at the American Urological Association 2011 annual meeting.
Hann-Chorng Kuo, MD, from Hualien, Taiwan, and colleagues conducted a study with 174 patients who received 100 U injections of intravesical botulinum toxin type A for refractory IDO. The investigators looked for acute urinary retention (AUR), large post-void residual (PVR, 150 mL), difficult urination, urinary tract infection (UTI), gross hematuria, and general weakness. They defined treatment success as a two-point improvement in patients' perception of their bladder condition. Success rates were determined at three and 24 months.
At three months, success was achieved by 138 patients (79.3%). However, large PVR developed in 81 patients (46.6%). Seventy-three patients (42%) needed to strain to void and 12 (6.9%) experienced AUR.
In addition, gross hematuria occurred in 17 patients (9.8%), UTI developed in 27 (15.5%), and general weakness was observed six (3.4%). AUR did not affect therapeutic results. Patients with large PVR and difficulty urinating had a significantly higher success rate. Conversely, those having UTI and hematuria after treatment were more likely have a less favorable outcome at three months. The 24-month success rates showed no significant differences between patients with and without AUR, large PVR, difficult urination, or UTI.