Hyperglycemia is a condition characterized by elevated levels of glucose in the blood. It often occurs in individuals with diabetes, particularly when their bodies do not produce enough insulin or cannot use it effectively. Common symptoms include increased thirst, frequent urination, and fatigue. If left untreated, hyperglycemia can lead to serious complications, such as diabetic ketoacidosis or long-term damage to organs like the kidneys and eyes. Managing blood sugar levels through diet, exercise, and medication is essential for preventing these complications and maintaining overall health.