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Hyperglycemia

Source: MedlinePlus Health Topics, U.S. National Library of Medicine

Last synced 8/15/2026Status: primary verified

What is blood glucose? Blood glucose , or blood sugar, is the main sugar found in your blood. It is your body's primary source of energy. It comes from the food you eat. Your body breaks down most of that food into glucose and releases it into your bloodstream. When your blood glucose goes up, it signals your pancreas to release insulin. Insulin is a hormone that helps the glucose get into your cells to be used for energy. For people with diabetes , your body doesn't make enough insulin, can't use it as well as it should, or both. Too much glucose stays in your blood and doesn't reach your cells. What is hyperglycemia? Hyperglycemia means high blood glucose. It most often affects people who have diabetes. When you have diabetes, your body doesn't make enough insulin or can't use it the right way. Too much glucose stays in your blood and doesn't reach your cells. What causes hyperglycemia? A key part of managing diabetes is controlling your blood glucose levels. To do this, you need to follow a diabetes meal plan and get regular physical activity . You might also need to take diabetes medicines . You have to balance all of these to keep your blood glucose at the right levels. But if you eat too much food or the wrong foods, don't take your medicines correctly, or don't get physical activity, you can get hyperglycemia. It can also happen if you are stressed or sick. Less commonly, people who don't have diabetes can also get hyperglycemia. It can be caused by conditions that can affect insulin or glucose levels in your blood. They include problems with your pancreas or adrenal glands , certain medicines, and severe illnesses. What are the symptoms of hyperglycemia? The symptoms of hyperglycemia include: Feeling thirsty Feeling tired or weak Headaches Urinating (peeing) often Blurred vision If you are diabetic and you often have high blood glucose levels or the symptoms of hyperglycemia, talk with your health care team. You may need a change in your diabetes meal plan,

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This information is for general education and is not medical advice. Always talk to a licensed U.S. clinician about your situation, medications, or treatment decisions.