Prior theoretical models of information seeking have examined its role, primarily, as a determinant of recommended behaviors. In this study, we develop and test the "behavior and risk information engagement" (BRIE) model, which accounts for the reciprocal effects of information seeking from interpersonal and media sources on two risk behaviors - nonmedical marijuana and amphetamine use. We test the model among young Israeli adults (N = 800) using a three-wave prospective observational study (at 6-month intervals). Autoregressive cross-lagged structural equation models showed good fit. Information seeking from interpersonal sources at baseline predicted amphetamine use and marijuana use at 6 months. In both models, seeking drug-related information from interpersonal sources at baseline was also a predictor of seeking information from media sources at 6 months. Information seeking from media sources at 6 months was also a significant predictor of amphetamine use at 12 months. Implications for theory and practice are discussed.