Objective: To examine nonmedical use (NMU) of prescription ADHD stimulants among adults evaluated for substance abuse treatment., Method: 147,816 assessments from the National Addictions Vigilance Intervention and Prevention Program (NAVIPPRO) system (10/01/2009 through 03/31/2012) examined NMU prevalence, routes of administration (ROA), and diversion sources., Results: Past 30-day NMU for prescription stimulants (1.29%) was significantly lower than that of prescription opioids (19.79%) or sedatives (10.62%). For stimulant products, NMU for Adderall was 0.62, followed by Adderall XR (0.42), Ritalin (0.16), Vyvanse (0.12), and Concerta (0.08); product differences likely have limited clinical relevance given the low estimates (<1%). Higher NMU per prescriptions was for Adderall (4.92), Ritalin (4.68), and Adderall XR (3.18) compared with newer formulations (Vyvanse 1.26, Concerta 0.89). Diversion source was mainly family/friends with no differences between products; swallowing whole was the most frequent ROA., Conclusion: Prescription stimulant NMU was low compared with other prescription medications among individuals assessed for substance abuse problems, with little difference among specific products., (© 2013 SAGE Publications.)