In this paper we estimate the causal impact of state Medicaid enrollment expansions and expenditures on state and local resources allocated to other public health programs and services. Using a quasi-experimental design with instrumental variables estimation, we find evidence that increased Medicaid spending leads to reduced governmental spending on other public health services, consistent with a crowd-out effect. Over 10 years, such crowd-out has the potential to diminish the health status improvements generated through health insurance coverage expansions.