Clinical effects of oxybutynin hydrochloride in the treatment of unstable bladder and overactive neurogenic bladder: a long-term clinical trial

Clinical effects and therapeutic usefulness of oxybutynin hydrochloride were evaluated in a long-term clinical trial on patients with unstable bladders and neurogenic bladders. Of the 46 patients entered into the trial, 37 were those diagnosed with an unstable bladder and 9 with a neurogenic bladder with overactive detrusor. In 37 of the cases (80%), the period of drug administration reached up to 12 weeks and in 16 cases (34%) the drugs were administered for more than 24 weeks. The average administration period was 165.9 days. The average total given dose was 1776.9 mg and average dose per day was 10.7 mg. Excellent and good responses were obtained in 76.3, 88.9 and 69.6% at 12 and 24 weeks after start of administration and at the time of discontinuing the drug, respectively. The cystometric changes at pre- and post-administration were evaluated on 23 cases and revealed a significant increase in volume at first sensation and maximum desire to void. Maximum resting intravesical pressure was significantly declined and uninhibited detrusor contractions were significantly suppressed. Side effects were noted in 11 of the 46 cases (23.9%), most of which were well tolerated by the patients. In 4 cases the drug had to be discontinued because of the side effects. Dry mouth was the most common side effect, occupying almost half of the incidents. No significant abnormality was noted on blood laboratory data, blood pressure or heart rate, following the drug administration. In one case slight increase in serum glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase was encountered, but its relationship with the drug was obscure. The clinical usefulness of this drug (excellent and good) was 78.9, 88.9 and 69.6% at 12 and 24 weeks after start of administration, and at the time of drug discontinuation, respectively. The present long-term trial proved that oxybutynin hydrochloride is an exceedingly effective and safe agent for clinical management of unstable bladder and overactive neurogenic bladder.