Previously published literature has estimated that approximately 16.5% of American adults have OAB, and up to 37% of OAB patients have concomitant urinary incontinence (OAB-wet). In fact, OAB is one the most common urologic disorders, accounting for more than 2 million physician office visits in the United States (2007). Nonneurogenic OAB is a symptom complex, which is defined by the International Continence Society standardization committee as urgency, with or without urgency incontinence, usually with frequency and nocturia, in the absence of proven infection or other obvious pathology. Urgency with at least one other symptom is essential to diagnose OAB and is the cornerstone component of OAB. To date, there is a paucity of validated instruments to define urinary urgency, and therefore, the diagnosis of OAB is based on patient symptomatology. Diagnosis does not rely on urodynamic findings or characteristics and therefore a thorough history and physical examination are essential. Treatment for this nonsurgical condition is therefore aimed toward symptom control. This review provides the reader with a better understanding of the voiding cycle and available medical treatment options for nonneurogenic overactive bladder (OAB). This review contains 11 figures, 7 tables, and 90 references. Key Words: anticholinergic, β3 agonist, botulinum toxin, chemodenervation, cialis, intradetrusor onabotulinumtoxinA, micturation cycle, mirabegron, overactive bladder, phosphodiesterase type 5 inhibitors, urinary retention