Hyperglycemia describes an unusually high level of glucose in the bloodstream and urine . In a person with a normal metabolism, the body releases insulin from the pancreas which encourages the absorption of glucose by the body's cells, where it is usually metabolized into fat. The most common cause of hyperglycemia is diabetes mellitus. However, it can also be caused by certain pharmaceuticals, like steroids. It is also often found in people suffering from a life-threatening critical condition, such as stroke.