Many chronically ill adults in the United States face high prescription medication costs, yet little is known about the strategies patients adopt to cope with these costs. Through a national survey of 4,055 adults taking prescription medications for one of five chronic diseases, we compared whether respondents cut back on necessities such as food or heat to pay for medications, increased debt, or underused medications because of cost. We also examined the sociodemographic and clinical correlates and differential use by different sub-groups of these three strategies. Overall, 31% of respondents reported pursuing at least one of the strategies over the prior 12 months. Twenty-two percent had cut back on necessities, 16% had increased their debt burden, and 18% had underused prescription drugs. Among patients who underused their medication, 67% also had cut necessities or increased debt. Although we found significant differences in the way patients with varying socio-demographic characteristics responded to medication cost pressures, use of all these strategies was especially common among patients who were low-income, in poor health, and taking multiple medications.