Diabetes mellitus is a metabolic disease that is characterized by chronic elevated blood glucose levels (hyperglycemia). Therefore, the main goal of diabetes management is to keep blood glucose levels within normal limits or a target range as much as possible. If diabetes is not well controlled, further challenges to health may occur. People with diabetes can measure blood sugar by various methods, such as with a glucose meter or a continuous glucose monitor, which monitors over several days. Glucose can also be measured by analysis of a routine blood sample. In addition to lifestyle modification, some individuals may need medications to adequately control their blood sugar levels. Other goals of diabetes management are prevention or treatment of complications that can result from the disease itself and from its treatment.