We employed the risk information seeking and processing (RISP) model to inform the design of antibiotic stewardship messages aiming at influencing intentions to seek or avoid antibiotic risk information. College-age respondents (N = 400) from a national sample viewed one of three versions of a RISP-informed message or no message (control group). Relative to the control group, all RISP-informed messages increased perceptions of information insufficiency. The most complete version of the RISP-informed message increased severity perceptions and information seeking intention and decreased information avoidance intention. Approaches to designing antibiotic stewardship messages are recommended accordingly.