Evaluation of a new once-daily formulation of oxbutynin for the treatment of urinary urge incontinence. Ditropan XL Study Group.

OBJECTIVES

To evaluate in a 1 6-center, single-treatment study once-daily controlled-release oxybutynin (Ditropan XL) for urinary urge incontinence.

METHODS

Two hundred fifty-six participants with urge incontinence or mixed incontinence with a significant urge component were treated. After baseline measurements, participants converting from conventional oxybutynin started Ditropan XL at their previous oxybutynin dose; others started at 5 mg/day. Doses were adjusted until participants reached a maintenance dose that produced continence or the best balance between continence and side effects. This dose was continued for 12 weeks. Effectiveness was assessed by urinary diaries.

RESULTS

Effectiveness was achieved across all doses studied (5 to 30 mg/day), with 70.8% of participants using maintenance doses of 5 to 15 mg/day. Mean urge incontinence episodes per week decreased from 18.8 at baseline to 3.9 in maintenance week 1, 2.7 in week 4, and 2.8 at the end of the study. For those participants who reported urge incontinence episodes at baseline but were free of urge incontinence at maintenance week 1, 31% remained free of urge incontinence at every subsequent assessment. Participants who converted from other medications showed symptomatic improvement after conversion. At some time during the study, 58.6% of participants reported dry mouth, with 23.0% of participants rating it moderate or severe. Only 1.6% of participants discontinued the medication because of dry mouth.

CONCLUSIONS

Ditropan XL treatment reduced the number of incontinence episodes. Maximum benefit was demonstrated by maintenance week 4 and was sustained through 12 weeks of maintenance therapy.