You've been reading about how to lower your blood sugar levels. It is possible for your blood sugar to go too low, however, especially with insulin or certain diabetes pills.

Low blood sugar, known as hypoglycemia, only occurs as a result of treating your diabetes. If you are not taking pills or insulin, you should not experience blood sugar that is too low. You have hypoglycemia when your blood sugar falls below 70mg/dl.

The most common causes of hypoglycemia are:

  • Taking too much insulin or diabetes medication
  • Not eating enough food at your meals or snacks
  • Missing or delaying your meal
  • Getting more exercise than usual, without changing your foods or medications.
  • Drinking alcohol without eating food

Certain symptoms will warn you that your blood sugar is getting dangerously low. Be on the lookout for:

  • Weakness
  • Feeling tired
  • Shaking
  • Sweating
  • Headache
  • Hunger
  • Nervousness or anxiety
  • Feeling irritable

What to do

If any of these symptoms occur and you have a blood sugar test kit available, check your blood sugar. (See Step 5: Monitor Your Blood Sugar.) If the level is low (70mg/dl), you need to treat your low blood sugar right away. Eat one of the following sugar-containing foods, which will provide you with about 15 grams of carbohydrate:

  • 3 glucose tablets
  • Half cup (4 ounces) of fruit juice or regular soda
  • 6 or 7 hard candies
  • 1 tablespoon of sugar

Wait about 15 minutes for the sugar to get into your blood. This wait can be hard because of the uncomfortable symptoms you are feeling, but if you eat too much sugar, you will make your blood sugar go too high.

If you don't feel better in 15 minutes:

  • Eat something with sugar in it again.
  • Check your blood sugar. If it has come into a safer range (over 70mg/dl), and your meal is more than an hour away, eat a snack that contains carbohydrate and protein. Examples include either cheese and crackers or a glass of milk.

This combination of steps will almost always bring your blood sugar into the safe range. If it doesn't work, call your doctor right away.

In summary

This method of treating low blood sugars is called the 15:15 rule. Eat 15 grams of carbohydrate and wait 15 minutes.

Remember: Use simple sugar first to get the situation under control. Eating candy with a lot of fat (like chocolate) might seem like a good idea, but it won't bring your blood sugar up fast enough.

People with diabetes should wear or carry I.D. information that emergency medical staff can find. If you are on medication that can cause hypoglycemia, always carry a sugar-containing snack like glucose tablets, lifesavers, or raisins.


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Review Date: 5/1/2006

Reviewed By: Alan Greene, M.D., F.A.A.P., Department of Pediatrics, Packard Children's Hospital, Stanford University School of Medicine; Chief Medical Officer, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

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