Handling hypoglycemia

Learn the symptoms for and ways to treat low blood sugar

handling hypoglycemia diabetes
Image: dolgachov/ iStock

Published: September, 2016

Hypoglycemia is a potentially dangerous condition in which blood sugar falls too low. Too much exercise, too little food or carbohydrates, a missed or delayed meal, or a combination of these factors can bring on hypoglycemia. Symptoms vary depending on the severity of the reaction, but commonly include

  • nervousness
  • sweating
  • feeling cold and clammy
  • trembling or shakiness
  • rapid heartbeat
  • lightheadedness
  • hunger
  • irritability.

If early symptoms aren't recognized and treated quickly, blood sugar levels may continue to fall, resulting in

  • drowsiness
  • weakness
  • blurred vision
  • slurred speech
  • confusion
  • clumsiness
  • personality change or strange behavior such as belligerence or silliness.

At its worst, hypoglycemia can cause seizures or coma.

Most people with type 2 diabetes don't have to worry about hypoglycemia. It may, however, occur in those who use insulin or take a diabetes medication known as a sulfonylurea. Changes in eating habits, such as dieting— especially if carbohydrates are reduced—or increased exercise can lead to hypoglycemia. Talk with your doctor before making any changes in your diet or increasing your exercise.

The 15/15 Rule to treat a low blood sugar

Familiarize yourself with the symptoms of hypoglycemia, so that if it occurs, you can take steps to treat it appropriately and prevent the problem from recurring.

If you think you're having an episode of low blood sugar, don't ignore your symptoms. If possible, test your blood sugar with a finger-stick test. If it is low, follow the 15/15 rule. Eat 15 grams of carbohydrate and wait 15 minutes. Here are some foods that will provide about 15 grams of carbohydrate to lower blood sugar:

  • eat three glucose tablets or four dextrose tablets
  • drink 4 to 6 ounces of fruit juice
  • drink 5 to 6 ounces (about half a can) of regular soda, such as Coke or Pepsi
  • eat five to seven Life Savers
  • eat 2 tablespoons raisins
  • eat six jelly beans.

Don't eat foods containing chocolate, peanut butter, nuts, or fats. Fat slows the body's absorption of carbohydrates, so foods with fat won't raise your blood sugar quickly enough. After the carbohydrate is eaten, wait about 15 minutes for the sugar to get into your blood. If you do not feel better within 15 minutes, more carbohydrate can be consumed. Your blood sugar should be checked to make sure it has come within a safe range.

For more information on living with type 2 diabetes, buy Healthy Eating for Type 2 Diabetes, a Special Health Report from Harvard Medical School.

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