Anticholinergics are commonly used for the treatment of frequency, urgency, and urge incontinence in women. Alpha-blockers have been shown to have a modulating effect on bladder smooth muscle but are not commonly used clinically for this indication. To evaluate the clinical effectiveness of each treatment as well as the combination therapy, we performed an open prospective study comparing these agents. Between September 1994 and October 1995, 34 women aged 28-91 (mean age, 62) received either 0.375 mg of sustained-release hyoscyamine twice a day or 2 mg doxazosin QHS prior to being crossed over to the other drug and/or the combination. Symptoms were assessed using an expanded American Urological Association (AUA) symptoms score, which included questions regarding incontinence at completion of each therapeutic phase. Evaluation included 6-channel urodynamics. All three therapies were noted to be effective in reducing AUA symptom scores. By urodynamic evaluation, a greater percentage of patients with increased voiding pressures or decreased compliance responded to doxazosin than hyoscyamine. Side effects were noted to be less prevalent with doxazosin than with the other therapies. There appears to be a significant role for alpha-blockers in the treatment of voiding symptoms in women.