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Hypoglycemia or low blood glucose

  • Hypoglycemia means that your blood glucose is low—generally below 70 mg/dL. Symptoms occur quickly and need to be treated as soon as possible.

    Low glucose levels vary from person to person, so it is important to ask your health care provider or diabetes educator what is too low for you.

    Causes Prevention

    Not enough food.

    Eat all your meals and snacks on time.

    More physical activity than usual.

    Avoid exercise during diabetes medicine peak time.

    Drinking alcohol without food.

    Always eat a snack or a meal when you drink.

    Too much diabetes medicine.

    Take only the dose that has been prescribed.



    It is best to be safe. It will not harm you if you take some glucose even if you just suspect that your blood glucose is low.

    Mild (one or more of the following):

    • sweating
    • shaking
    • feeling weak/tired
    • feeling anxious or nervous feeling
    • racing heart
    • feeling hungry
    • having a mild headache
    • tingling sensation around lips and tongue


    A medical identification bracelet or necklace with "Diabetes" on it can help people help you if you can't help yourself. Although not as easily noticed, you can carry a card in your purse or wallet that says you have diabetes.

    More severe:

    • glassy eyes or staring
    • slurred speech
    • confusion
    • staggering walk

    Very severe (rare):

    • loss of consciousness
    • seizures


    Test your blood glucose as soon as you feel symptoms.

    If your level is low, treat with 15 grams of carbohydrate. Examples include:

    • 1/2 cup of fruit juice (you don't need to add sugar) 
    • 1/2 cup of regular pop 
    • 7 to 8 Lifesavers® or other candies 
    • 1 tablespoon of honey or sugar
    • 2 tablespoons of raisins
    • 3 large marshmallows
    • 1 cup of skim milk
    • 4 glucose tablets
    • 15 grams of glucose gel

    Retest your blood glucose every 15 minutes until your blood glucose is above 80 mg/dL without symptoms.

    Food needs after a hypoglycemic event

    After a hypoglycemia event you may need more food:

    • If your next meal or snack is less than one hour away, don't make any changes.
    • If your next meal or snack is 1 to 2 hours away, eat a piece of fruit, or six saltines, or drink 1 cup of skim milk, or eat any food that contains 15 grams of carbohydrate.
    • If your next meal or snack is more than two hours away, eat a piece of fruit plus 1 cup of skim milk, or 1 cup of fruit juice or any food that contains 30 grams of carbohydrate.

    Things to remember

    Do not subtract what you eat to treat hypoglycemia from your next snack or meal. This food is needed to keep your blood glucose in a better range.

    Also, if you have unexplained hypoglycemia often (two times in 1 day or 2 days in a week), call your health care provider or diabetes educator.

    Insulin, hypoglycemia and driving

    If you take insulin, always check your blood glucose before you drive.

    • Do not drive if your blood glucose is lower than 80 mg/dL.
    • If your blood glucose is between 80 and 100 mg/dL, eat 10 to 20 grams of fast-acting glucose.
    • Increase your carbohydrates for longer drives.
    • Always keep a fast-acting carbohydrate in your vehicle.


    If you are on insulin, you may be required by state law to submit a special document from your health care provider stating you can drive safely. Talk to your health care provider if you have questions.

    You can also check the Department of Public Safety or Department of Transportation website for your state’s requirements.

    If you live in Minnesota, please visit:

    • Type "diabetes" in the search box to find more information.

    If you live in Wisconsin, please visit:

    • Type "diabetes" in the search box to find more information.
  • Source: Allina Health's Patient Education Department, Basic Skills for Living with Diabetes, sixth edition
    Reviewed by: Allina Health's Patient Education Department experts
    First published: 12/01/2006
    Last reviewed: 01/09/2015

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