Objectives. Detrusor hyperreflexia with elevated storage pressures presents a major risk factor for renal damage in patients with neurogenic lower urinary tract dysfunction. If standard anticholinergic treatment is unsuccessful, surgical treatment must be considered. We evaluated the effects of intravesical oxybutynin treatment on detrusor hyperreflexia in patients in whom standard oral treatment had failed.

Methods. Twenty-five patients (mean age 36.7 years) with storage pressures greater than 40 cm H₂O despite standard anticholinergic treatment received intravesical (15 mg three times daily) and oral oxybutynin chloride treatment. The follow-up evaluations included urodynamic testing, renal ultrasound, urine examination (urinalysis and urine culture), and evaluation of side effects.

Results. The mean follow-up was 6 months. Intravesical treatment led to an increase in bladder storage volume from 349 to 420 mL. The mean maximum storage pressure was significantly reduced from 54 to 26.5 cm H₂O. Detrusor storage pressures returned to values less than 40 cm H₂O in 21 of 25 patients. Dysreflexia was treated successfully in 3 of 5 patients. No patient developed renal damage. No severe side effects or drug-related discontinuation of treatment were observed.

Conclusions. Intravesical oxybutynin therapy seems to be a safe and effective treatment option for detrusor hyperreflexia in adults and avoids surgical treatment in most patients. Long-term observations concerning side effects, acceptance, and efficacy are needed.