This study will design an alternative urodynamic platform to better evaluate treatment effects of medications for overactive bladder. Part II is dependent on results of Part I and may not be conducted.

Inclusion Criteria:

• Patient is a postmenopausal female 40 to 75 years of age
• Patient has a Body Mass Index (BMI) less than or equal to 35 kg/m2
• Patient has a documented history of overactive bladder for at least 6 months prior to screening

Exclusion Criteria:

• Patient has stress or mixed incontinence
• Patient has a history of interstitial cystitis, painful bladder syndrome, or chronic pelvic pain
• Patient has a history of stroke, seizures, or major neurological disorders
• Patient has a history of fecal incontinence
• Patient has a history of continual urine leakage
• Patient has had surgery to correct stress urinary incontinence or pelvic organ prolapse within 6 months of study start
• Patient received bladder training of electrostimulation within 2 weeks of study start
• Patient requires a catheter
• Patient is taking medications that cannot be stopped for the duration of the trial including certain anticholinergics or smooth muscle relaxants
• Patient began taking tricyclic antidepressants, serotonin/norepinephrine reuptake inhibitors, calcium channel blockers, ephedrine/pseudoephedrine, or diuretic therapy less than 8 weeks before study start
• Patient has been on hormone replacement therapy for less than 12 weeks at study start
• Patient must take medication for arrhythmia
• Patient consumes more than 2 alcoholic beverages per day
• Patient consumes more than 3 servings of caffeinated beverages per day (1 serving = 120 mg caffeine)
• Patient has multiple and/or severe allergies to foods and drugs
• Patient regularly uses any illegal drugs

The adverse experiences reporting are from the randomization visit to follow-up phone call.

Urinalysis and vital sign measurements were performed to monitor safety at clinic visits. Patients were also, queried for any adverse experiences at each visit.

The analysis presented includes all patients. An analysis excluding patients who were misdosed yielded different results with a similar conclusion and are not presented.