More frequent long-term opioid use was seen among adults with attention-deficit/hyperactivity disorder (ADHD) if they were taking stimulants, an observational study of Medicaid prescription data found. Opioid use (>=30 days) was seen among 16.5% of those who used stimulants, compared with 13% of those who did not, reported Yu-Jung Jenny Wei, PhD, of the University of Florida in Gainesville, and colleagues.