There has been increased attention on the importance of identifying and distinguishing the differences between stress-induced hyperglycemia (SH), newly diagnosed hyperglycemia (NDH), and hyperglycemia in persons with established diabetes mellitus (DM). Inpatient blood glucose control is now being recognized as not only a cost issue for hospitals but also a concern for patient safety and care. The reasons for the increased incidence of hyperglycemia in hospitalized patients include preexisting DM, undiagnosed DM or prediabetes, SH, and medication-induced hyperglycemia with resulting transient blood glucose variability. It is clear that identifying and documenting hyperglycemia in hospitalized patients with and without a previous diagnosis of DM and initiating prompt insulin treatment are important. Agreement on the optimum treatment goals for hyperglycemia remains quite controversial, and the benefits of intensive glucose management may be lost at the cost of hypoglycemia in intensive care unit patients. Nutrition support in the form of enteral nutrition (EN) increases the risk of hyperglycemia in both critical and non-critically ill hospitalized patients. Reasons for beginning a tube feeding are the same whether a person has NDH or DM. What differs is how to incorporate EN into the established insulin management protocols. The risk for hyperglycemia with the addition of EN is even higher in those without a previous diagnosis of DM. This review discusses the incidence of hyperglycemia, the pathogenesis of hyperglycemia, factors contributing to hyperglycemia in the hospitalized patient, glycemic management goals, current glycemic management recommendations, and considerations for EN formula selection, administration, and treatment.