Fuente: PubMed "Cannabis" Addict Behav. 2026 Mar 25;179:108682. doi: 10.1016/j.addbeh.2026.108682. Online ahead of print.ABSTRACTINTRODUCTION: Specific sources for nonmedical prescription stimulant use (NMPSU) are linked to different rates of concurrent substance use (e.g., cannabis use) in adolescents and young adults. This study investigates whether NMPSU sources at age 17-18 (baseline) are linked to greater odds of NMPSU over young adulthood (19-30 years) and whether sources are consistent across development.METHODS: Data were from the 2007-2020 longitudinal Monitoring the Future panel study, with 1244 observations from 876 unique participants with any past-year NMPSU source data. NMPSU sources included given for free, theft, purchases, from one's own prescription, or other sources. Multiple source use was also captured. Analyses estimated NMPSU sources by age group (17-18 vs. 19-30) and NMPSU and source use at ages 19-30 based on NMPSU sources at ages 17-18.RESULTS: When compared to older adolescents, young adults were more likely to obtain stimulant medication from peers or family for free (adjusted odds ratio [aOR] = 1.58, 95% confidence interval (95% CI) = 1.10, 2.28), while NMPSU from one's own prescription (aOR = 0.39, 95% CI = 0.23, 0.65) and other source use (aOR = 0.38, 95% CI = 0.21, 0.69) were less common. Sources at ages 17-18 did not predict prevalence of past-year NMPSU at ages 19-30; similarly, sources were not consistent across the study period.CONCLUSIONS: NMPSU sources in late adolescence were not related to NMPSU in young adulthood, and sources were not consistent. Stimulant medication sources may be a better indicator of current risky behavior than of longer-term substance use.PMID:41916200 | DOI:10.1016/j.addbeh.2026.108682