OBJECTIVES: Antimuscarinic agents are the first line of treatment for overactive bladder (OAB). However, little is known regarding the utilization pattern of antimuscarinic agents in the elderly with OAB. This study examined the prevalence and predictors of antimuscarinic prescribing in elderly OAB patients using national ambulatory survey data. METHODS: This cross-sectional study utilized 2009-2010 National Ambulatory Medical Care Survey (NAMCS) and outpatient component of National Hospital Ambulatory Medical Care Survey (NHAMCS). The study sample included patients aged ≥65 years diagnosed with OAB. Antimuscarinic medications were operationally defined using the American Hospital Formulary Service (AHFS) classification and identified using Multum lexicon codes. Descriptive statistics using sampling weights were used to estimate the prevalence of antimuscarinic medication use. Multivariable logistic regression within the conceptual framework of Anderson Behavioral Model was used to identify the factors associated with antimuscarinic medication use in elderly OAB patients. RESULTS: According to the national surveys, 2.18 (95% Confidence Interval, 95% CI: 1.62-2.75) million elderly outpatient visits were made for OAB; an estimated 0.90 million of these visits (41.43%) involved prescribing of antimuscarinic medications. The most frequently prescribed drugs were solifenacin (14.25%), oxybutynin (10.50%) and tolterodine (6.89%). Multivariable analysis revealed that age between 65 to 74 years (Odds Ratio, OR: 0.29; 95% CI: 0.10-0.81) decreased the likelihood of receiving antimuscarinic medications, whereas South region (OR: 2.78; 95% CI: 1.02-7.59) increased the likelihood of receiving antimuscarinic medications in elderly OAB patients. CONCLUSIONS: The study found that less than half of the elderly OAB visits involved use of   antimuscarinic medications. The study also found variation in antimuscarinic use across age and region. Given the anticholinergic effects of antimuscarinic agents, there is a need to further evaluate safety profile of the antimuscarinic agents, especially in the elderly.