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    Diabetes: Preventing High Blood Sugar Emergencies

    Diabetes: Preventing High Blood Sugar Emergencies


    High blood sugar (hyperglycemia) in diabetes occurs when the sugar (glucose) level in the blood rises above normal. For a person who has diabetes, high blood sugar may be caused by not getting enough insulin, missing your diabetes medicine, eating too much food, skipping exercise, or being ill or stressed.

    Unlike low blood sugar, high blood sugar usually develops slowly over hours or days. Blood sugar levels well above your target range may make you feel tired and thirsty. If your blood sugar continues to rise, your kidneys will produce more urine and you can become dehydrated . Signs of dehydration include being thirstier than usual and having darker urine than usual. If you become severely dehydrated, you can go into a coma and possibly die. Over time, high blood sugar damages the eyes, heart, kidneys, blood vessels, and nerves.

    Unless you fail to notice the symptoms, you usually have time to treat high blood sugar so that you can prevent an emergency. Three things can help you prevent high blood sugar problems:

    • Test your blood sugar often, especially if you are sick or not following your normal routine. You can see when your blood sugar is above your target range, even if you don't have symptoms of high blood sugar (increased thirst, increased urination, and fatigue). Then you can treat it early.
    • Call your doctor if you have frequent high blood sugar or your blood sugar is consistently above your target range. Your medicine may need to be adjusted or changed.
    • Drink extra water or noncaffeinated, nonsugared drinks to prevent dehydration.

    How To

    The best way to prevent a high blood sugar emergency is to keep it from developing.

    Treat infections early

    Untreated infections (such as urinary tract infections, pneumonia, and skin infections) can increase your risk for a high blood sugar emergency.

    Be prepared

    • Know the symptoms of high blood sugar, such as increased thirst, increased urination, and fatigue. Post a list of the symptoms in a place where you can see it often, such as on your refrigerator door. Add any symptoms you have noticed that may not be on the list. Make sure other people know the symptoms and what to do in case of an emergency.
    • Check your blood sugar at home often, especially if you are sick or not following your normal routine. If you don't have a blood sugar meter, talk with your doctor about getting one. It is easy to overlook early symptoms, especially if you have increased urination without increased thirst. Testing your blood sugar at home will help you know when it is high, even if you do not notice symptoms.
    • Teach others (at work and at home) the symptoms of high blood sugar. Teach others to call 911 if you are unconscious or too sick to check your own blood sugar.
    • Wear medical identification. Have a medical alert bracelet or other form of medical jewelry with you at all times. This is very important in case you are too sick or injured to speak for yourself. You can find medical identification at a pharmacy or on the Internet.
    • If you take insulin, test for ketones, especially if your blood sugar is higher than 300 mg/dL.
    • Develop a plan. Usually people who take insulin need to take extra fast-acting insulin when their blood sugar levels are high. Talk with your doctor about how much to take, depending on your blood sugar level (sliding scale).
    • Take your medicines as prescribed. Don't skip diabetes medicine or insulin doses without first talking with your doctor.

    Treat high blood sugar early

    The best way to prevent high blood sugar emergencies is to treat high blood sugar as soon as you have symptoms or when your blood sugar is significantly above a target range (200 mg/dL or higher).

    • Follow your doctor's instructions for the steps for dealing with high blood sugar. Post a list of the steps in a convenient place at home and work. Make sure other people know what to do if you are unable to treat high blood sugar.
    • Keep a record (What is a PDF document?) of high blood sugar levels. Write down your symptoms and how you treated them, and take it with you when you visit your doctor.
    • Call your doctor. Let your doctor know if you are having high blood sugar problems. Your diabetes medicine may need to be adjusted or changed. If you are taking insulin, your dose of insulin may need to be increased.

    Drink plenty of liquids

    If your blood sugar levels are above your target range, drink extra liquids to replace the fluids lost through your urine. Water and sugar-free drinks are best. Avoid caffeinated drinks, alcohol, and soda pop and other liquids that contain a lot of sugar, such as fruit juice.


    Other Works Consulted

    • Inzucchi SE, et al. (2012). Management of hyperglycemia in type 2 diabetes: A patient-centered approach. Diabetes Care, 35(6): 1364-1379.
    • Kitabchi AE, et al. (2009). Hyperglycemic crises in adult patients with diabetes. Diabetes Care, 32(7): 1335-1343.


    By Healthwise Staff
    E. Gregory Thompson, MD - Internal Medicine
    Rhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator
    Last Revised August 15, 2013

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