This study examined age-related differences in medication risk-taking and the effects of collaboration on individual risk-taking. We recruited 24 younger and 24 older adults, and asked them to choose between medications that differed in probabilities and outcomes of treatment success. Participants chose between a risky option and a sure option that had equal expected values (risk-neutral) and between a risky option and a sure option that had a lower expected value (risk-advantageous). Participants completed the decision task first individually (pre-collaboration), then in dyads (collaboration), and once again individually (post-collaboration). During pre-collaboration older adults showed a smaller increase in risk-taking tendency in response to risk-advantageous trials compared to younger adults. Older adults’ risk preferences converged towards their partner’s preference to a greater extent following collaboration relative to younger adults. These findings highlight the importance of designing decision aids for older adults, and considering how social processes influence patients’ medication decisions.