Detrusor overactivity is the most common cause of UI in the elderly, occurring in 40% to 70% of those who present to the physician with complaints of incontinence. Patients with detrusor overactivity have early, forceful detrusor contractions, which occur well before the bladder is full. This creates its clinical hallmark “the abrupt sensation that urination is imminent, whether or not leakage ensues” and frequency. Patients with detrusor overactivity describe frequent losses of small to moderate volumes of urine. The PVR urine volume is typically normal (100 mL).