A randomized, double-blind placebo-controlled trial of the effects of the 5-hydroxytriptamine(4) agonist cisapride on the female urinary bladder.

Objective: Anecdotal reports have proposed the use of the 5-hydroxytriptamine(4) agonist cisapride as a treatment for female voiding dysfunction on the basis of the known prokinetic actions of the medication. The purpose of our study is to assess the effects of this agent on the normal bladder in vivo.

Study Design: In this randomized, double-blind placebo-controlled trial, patients were randomized to receive either 20 mg cisapride or an identical placebo. They then underwent urodynamic evaluation that included uroflowmetry, multichannel filling cystometry, pressure-flow studies, and a urethral pressure profile. After a washout period of at least 7 days, subjects were then crossed over to the other arm and the tests were repeated.

Results: Twenty women without significant urinary incontinence agreed to participate. There was a decrease in the maximum cystometric capacity from 556 mL for placebo to 496 mL for cisapride (P <.001). There was no difference in the detrusor pressure at maximum flow, the maximum detrusor pressure, the flow rate, or the percentage of maximum cystometric capacity voided.

Conclusions: In healthy women, cisapride caused a significant decrease in the maximum cystometric capacity, which could account for the higher reported rates of urinary frequency and urgency with this medicine. There was no evidence that this prokinetic agent improved voiding function.