What do i do if blood sugar is high

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High blood sugar, also called hyperglycemia, affects people who have diabetes. Several factors can play a role in hyperglycemia in people with diabetes. They include food and physical activity, illness, and medications not related to diabetes. Skipping doses or not taking enough insulin or other medication to lower blood sugar also can lead to hyperglycemia.

It's important to treat hyperglycemia. If it's not treated, hyperglycemia can become severe and cause serious health problems that require emergency care, including a diabetic coma. Hyperglycemia that lasts, even if it's not severe, can lead to health problems that affect the eyes, kidneys, nerves and heart.

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Symptoms

Hyperglycemia usually doesn't cause symptoms until blood sugar (glucose) levels are high — above 180 to 200 milligrams per deciliter (mg/dL), or 10 to 11.1 millimoles per liter (mmol/L).

Symptoms of hyperglycemia develop slowly over several days or weeks. The longer blood sugar levels stay high, the more serious symptoms may become. But some people who've had type 2 diabetes for a long time may not show any symptoms despite high blood sugar levels.

Early signs and symptoms

Recognizing early symptoms of hyperglycemia can help identify and treat it right away. Watch for:

• Frequent urination
• Increased thirst
• Blurred vision
• Feeling weak or unusually tired

Later signs and symptoms

If hyperglycemia isn't treated, it can cause toxic acids, called ketones, to build up in the blood and urine. This condition is called ketoacidosis. Symptoms include:

• Fruity-smelling breath
• Dry mouth
• Abdominal pain
• Nausea and vomiting
• Shortness of breath
• Confusion
• Loss of consciousness

When to see a doctor

Seek immediate help from your care provider or call 911 if:

• You have ongoing diarrhea or vomiting, and you can't keep any food or fluids down
• Your blood glucose levels stay above 240 mg/dL (13.3 mmol/L) and you have symptoms of ketones in your urine

Make an appointment with your health care provider if:

• You have ongoing diarrhea or vomiting, but you're able to take some foods or drinks
• You have a fever that lasts more than 24 hours
• Your blood sugar levels stay above 240 mg/dL (13.3 mmol/L) despite treatment, and you have symptoms of ketoacidosis
• You have trouble keeping your blood glucose within your target range

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