Clin Ther. 2004 Jul;26(7):1026-36.

A randomized, double-blind, parallel-group comparison of controlled- and immediate-release oxybutynin chloride in urge urinary incontinence.

Barkin J, Corcos J, Radomski S, Jammal MP, Miceli PC, Reiz JL, Harsanyi Z, Darke AC; UROMAX Study Group.

University of Toronto, Toronto, Ontario, Canada.


The aim of this study was to evaluate the efficacy and safety of a new PO controlled-release (CR) QD oxybutynin tablet relative to PO immediate-release (IR) TID oxybutynin in patients with urge urinary incontinence (UI).


In this multicenter, double-blind trial, patients with UI (> or = 7 episode/wk) and Frequency (> or = 8 micturitions/d) were randomized to CR or IR oxybutynin for 6 weeks. Patients initiated treatment at 15 mg/d and the dose was adjusted (in 5-mg/d increments) over 2 weeks according to tolerability. Efficacy (UI episodes, voids, absorbent pads used, urgency, and volume voided per micturition) was assessed during the final 2 weeks of treatment. Tolerability was assessed by evaluating adverse events and treatment withdrawals.


Of the 125 patients randomized, 94 (75%) were evaluable for efficacy; tolerability was assessed in all patients. In the CR group, 48 patients (91%) were women and 5 (9%) were men; the mean (SD) age was 58.0 (12.4) years (range, 26-78 years). In the IR group, 37 patients (90%) were women and 4 (10%) were men; the mean (SD) age was 60.6 (14.8) years (range, 26-83 years). Both CR and IR oxybutynin significantly reduced the mean number of total UI episodes per week (both P < 0.001 vs baseline). Both treatments produced e quivalent reductions in mean voiding Frequency and urinary urgency (all P < 0.001 vs. baseline). Significantly more patients rated CR oxybutynin tolerable on the initial dose of 15 mg/d (P = 0.020) and completed the study at a dose of > or = 15 mg/d (P = 0.018). Dry mouth was the most common adverse event, reported by 68% and 72% of patients in the CR and IR oxybutynin groups, respectively.


Among the patients with urge UI included in this study, CR oxybutynin was as effective as IR oxybutynin for improving primary symptoms, with the additional benefit of QD administration.

Women's Health

Please click on the required question.

Women's Health

Thank you for choosing to visit us.

This is the personal website of David A Viniker MD FRCOG, retired Consultant Obstetrician and Gynaecologist - Specialist Interests - Reproductive Medicine including Infertility, PCOS, PMS, Menopause and HRT.
I do hope that you find the answers to your women's health questions in the patient information and medical advice provided.

I do hope that you find the answers to your women's health questions in the patient information and medical advice provided.

The aim of this web site is to provide a general guide and it is not intended as a substitute for a consultation with an appropriate specialist in respect of individual care and treatment.

David Viniker retired from active clinical practice in 2012.
In 1999, he setup this website - - to provide detailed
information many of his patients requested. The website attracts thousands of visitors every day from around the world.
Website optimisation (SEO) has became more than an active hobby. If you would like advice on your website, please visit his website Keyword SEO PRO or email him on
David Viniker Linkedin Profile