The mechanisms used by Medicare beneficiaries who reached their Part D drug-benefit threshold to cope with the costs of prescription drugs were evaluated. A retrospective review of integrated medical and pharmacy electronic records and a mail survey were utilized. Members of a Medicare Advantage plan continuously enrolled in 2006 in either a standard drug-benefit plan who reached their threshold by October 1, 2006 (study group) or a retiree drug subsidy plan without a threshold but by October 1, 2006, had reached the threshold in total drug spend (control group) were included. Data on members' cost-lowering medication strategies, demographics, and socioeconomic status were analyzed. Of the 1,472 questionnaires mailed, 622 (42%) were completed. Respondents in the study group were more likely than control respondents to be male, be married, own a home, report lower health status, and have a household income of <$30,000 (p < 0.05). There were no significant differences in age, race or ethnicity, and diagnoses between groups. Study group respondents were three times more likely than control group respondents to use a cost-lowering strategy (p < 0.001). Predictors of increased risk of using a medication cost-lowering strategy included study group assignment, age, health status, education, income, and purchase of a second-generation antipsychotic (p < 0.05). Respondents in the study group were three times more likely than respondents in the control group to report using a medication cost-lowering strategy. Respondents who were younger and had limited prescription drug coverage, lower household income, higher educational status, and poorer health status were at increased risk of adopting a cost-lowering strategy.