Cardozo L and Dixon A (2005) Increased warning time with darifenacin: a new concept in the management of urinary urgency. J Urol 173: 1214–1218

A recent paper by Cardozo and Dixon is one of the first studies to assess the effect of darifenacin—a selective M3-receptor antagonist developed for overactive bladder syndrome—on the warning time associated with urinary urgency.

This multicenter, double-blind, placebo-controlled study included 72 subjects who had had symptoms of urgency for 6 months or greater and four or more episodes of urgency per day. Subjects were randomized in a 1:1 ratio to receive darifenacin (30 mg once daily) or placebo for 2 weeks. Electronic event recorders were used to monitor urge–void cycles in a 6 h period in the clinic, and subjects were instructed in the use of a paper diary and asked to complete this at home.

Warning time (defined as the time from the first sensation of urgency to voluntary incontinence) was significantly longer in the darifenacin-treated patients compared with placebo. Darifenacin-treated patients also achieved a significant decrease in the severity of urgency compared with placebo; however, this was only shown during clinic-centered monitoring periods. Only mild or moderate adverse events were reported.

Limitations of this study included the small number of subjects and short treatment duration. The authors conclude, however, that treatment with darifenacin significantly increased mean, median and minimum warning times compared with placebo. This should confer a decrease in incontinence episodes and, therefore, increase subject confidence. The authors note that future follow-up studies are needed to determine the degree of increase in warning time needed to significantly enhance quality of life in these patients.