Efficacy and safety of transdermal oxybutynin in patients with urge and mixed urinary incontinence.
OBJECTIVE
We evaluated the efficacy and safety of an oxybutynin transdermal delivery system (TDS) in a general population of patients with overactive bladder and urge or mixed urinary incontinence.


METHODS
Following symptom stabilization or treatment withdrawal 520 adult patients were randomized to 12 weeks of double-blind daily treatment with 1.3, 2.6 or 3.9 mg. oxybutynin TDS or placebo administered twice weekly, followed by a 12-week open-label, dose titration period to assess efficacy and safety further. Evaluations included patient urinary diaries, incontinence specific quality of life and safety.


RESULTS
A dose of 3.9 mg. daily oxybutynin TDS significantly reduced the number of weekly incontinence episodes (median change -19.0 versus -14.5, p = 0.0165), reduced average daily urinary frequency (mean change -2.3 versus -1.7, p = 0.0457), increased average voided volume (median change 24 versus 6 ml., p = 0.0063) and significantly improved quality of life (Incontinence Impact Questionnaire total score, p = 0.0327) compared with placebo. Average voided volume increased in the daily 2.6 mg. group (19 ml., p = 0.0157) but there were no other significant differences between 1.3 and 2.6 mg. oxybutynin TDS and placebo. The most common adverse event was application site pruritus (oxybutynin TDS 10.8% to 16.8%, placebo 6.1%). Dry mouth incidence was similar in both groups (7.0% versus 8.3%, p not significant). In the open-label period a sustained reduction of nearly 3 incontinence episodes per day was reported for all groups.


CONCLUSIONS
Doses of 2.6 and 3.9 mg. oxybutynin TDS daily improve overactive bladder symptoms and quality of life, and are well tolerated. Transdermal oxybutynin is an innovative new treatment for overactive bladder.
Dmochowski
Roger R
RR
Urology Associates of North Texas, Fort Worth, Texas, USA.
Davila
G Willy
GW
Zinner
Norman R
NR
Gittelman
Marc C
MC
Saltzstein
Daniel R
DR
Lyttle
Sydney
S
Sanders
Steven W
SW
D000279:Administration, Cutaneous; D000328:Adult; D000368:Aged; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008333:Mandelic Acids / Q000008:administration & dosage* / Q000009:adverse effects; D008875:Middle Aged; D009122:Muscle Hypertonia / Q000188:drug therapy / Q000209:etiology; D011788:Quality of Life; D016896:Treatment Outcome; D014549:Urinary Incontinence / Q000188:drug therapy* / Q000209:etiology; D014563:Urodynamics / Q000187:drug effects
D008333:Mandelic Acids; C005419:oxybutynin