Hypoglycemia, or low blood glucose, is a condition in which there is too much insulin and not enough glucose (a simple sugar) in your body. (You may also have heard hypoglycemic reaction called "insulin reaction.") Hypoglycemia can only occur in people who take insulin or an oral diabetes medication to manage diabetes. People who control their blood glucose levels through diet and exercise do not develop hypoglycemia.

What are the causes of hypoglycemia?
The causes of hypoglycemia include:

  • Missing a meal or not eating the whole meal
  • Exercising more than usual
  • Not eating when ill
  • Eating later than usual
  • Taking too much diabetes medication (insulin or oral diabetes medication)
  • Drinking alcohol

What are the symptoms of hypoglycemia?
Most people feel symptoms of hypoglycemia when their blood glucose is 70 mg/dl or lower.

Each person may have different symptoms of hypoglycemia. You will learn to recognize your symptoms. Hypoglycemia symptoms include:

Early symptoms

  • Confusion
  • Dizziness
  • Feeling shaky
  • Hunger
  • Headaches
  • Irritability
  • Pounding heart
  • Pale skin
  • Sweating
  • Trembling
  • Weakness

Late symptoms

  • Headache
  • Feeling irritable
  • Poor coordination
  • Poor concentration
  • Nightmares or bad dreams
  • Numbness in the mouth and tongue
  • Passing out
  • Coma

How is hypoglycemia treated?
When you have symptoms of hypoglycemia:

1. Check your blood glucose level.

2. If your blood glucose is less than 65 to 70 mg/dl, or if you have symptoms of hypoglycemia, eat a food that contains glucose*, such as:
- Two or three glucose tablets (available at pharmacy)
- 4 to 6 pieces of hard candy (not sugar-free)
- 1/2 cup of orange or apple juice
- 1 cup of skim milk
- 1/2 cup soft drink (not sugar-free)
- 1 tbsp honey
- 1 tbsp brown sugar
- 1 tbsp corn syrup

*Eat only one of the foods listed, in the amount given.

Important: If you take an alpha-glucosidase oral diabetes medication, low blood glucose can only be treated with glucose tablets or gel.

3. Fifteen minutes after you have eaten one of the above choices, check your blood glucose level. If your blood glucose is less than 70 mg/dl or if you have symptoms of hypoglycemia, eat another serving of one of the above choices. If it is more than 45 minutes until your next meal, eat a snack such as a peanut butter sandwich or cheese and crackers to prevent another reaction.

4. Keep a record of the date and time of day your reaction occurred and what you did.

5. Call your doctor if you have more than one unexplained hypoglycemic reaction in a week.

6. Wear a medical identification tag (for example, Medic Alert) and/or carry an identification card that states that you have diabetes.

7. Hypoglycemia may cause you to pass out. If so, you will need someone to give you a Glucagon injection. It is important that your family members and/or friends know how to give you the injection in case you have a low blood glucose reaction. Talk with your doctor, nurse, or diabetes educator about the use of Glucagon.

Note: It is very dangerous to drive during a low blood glucose reaction. If you are driving and you experience symptoms of hypoglycemia, safely pull off the road and eat a glucose-containing food. Wait at least 15 minutes and repeat the treatment, if necessary, before continuing to your destination. It is important to keep a glucose source and a snack in your car for emergencies.

How can I prevent hypoglycemia?

  • Follow your meal plan.
  • Eat at least three, evenly spaced meals each day with between-meal snacks as prescribed.
  • Plan for your meals to be no more than 4 to 5 hours apart.
  • Exercise 1/2 to 1 hour after meals.
  • Double-check your insulin and oral glucose-lowering medication dose before taking it.
  • Know when your medicine is at its peak level.
  • Carry a glucose source with you at all times. It is important to keep a glucose source in your car for emergencies.
  • Test your blood glucose as often as directed by your health care provider.
  • Make sure a family member or friend knows how to give you a Glucagon injection in cases of severe hypoglycemia when you may not be conscious.

What are the effects of low blood glucose on the body?
The effects of low blood glucose are of particular concern for people who have type 1 diabetes. For these people, intensive treatment of diabetes with insulin can prevent or delay life-threatening complications, but it also makes episodes of low blood glucose more likely to occur.

Prolonged episodes of low blood glucose present a risk to your health. It is very important to recognize the warning signs of low blood glucose and to treat it promptly.

Talk with your doctor if you have more than one unexplained low blood glucose reaction in one week.

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