Actionsets help people take an active role in managing a health condition.  Dealing with low blood sugar from insulin for diabetes

What? - What is the medical information or key concepts related to the action? What is a low blood sugar (hypoglycemia) emergency?

Low blood sugar (hypoglycemia) means that the level of sugar (glucose) in your blood has dropped below what your body needs to function normally. When your blood sugar level drops below 70 milligrams per deciliter (mg/dL), you most likely will have symptoms, such as feeling tired, weak, or shaky. Symptoms of low blood sugar can develop quickly.

  • If your blood sugar level drops just slightly below a safe range, you may have symptoms of mild low blood sugar. If you eat something that contains sugar, these symptoms may last only a short time. If you have had diabetes for many years, you may not always notice symptoms of mild low blood sugar. This is called hypoglycemia unawareness.
  • If your blood sugar level continues to drop (usually below 40 mg/dL), your behavior may change. Symptoms of moderate low blood sugar may develop. You may become too weak or confused to eat something to raise your blood sugar level.
  • If your blood sugar level drops very low (usually below 20 mg/dL), you may lose consciousness or have a seizure. If you have symptoms of severe low blood sugar, you need medical care immediately.

Sometimes people with diabetes have low blood sugar levels during the night. If your blood sugar level drops during the night, you may wake up in a cold sweat and feel weak, or you may sleep through it. Your body may use stored sugar to raise your blood sugar level back toward a safe range. If this happens, you most likely will wake up in the morning with a headache and possibly high blood sugar.

What causes low blood sugar?

Low blood sugar (hypoglycemia) can develop rapidly (within 10 to 15 minutes). It can occur if you:

  • Take too much insulin.
  • Skip or delay a meal or snack.
  • Exercise too much without eating enough food.
  • Drink too much alcohol, especially on an empty stomach.
  • Take certain medications that lower blood sugar. Some medications that you can buy without a prescription can affect blood sugar levels. Talk with your health professional about your prescription and nonprescription medications and whether they may increase your risk of developing very low blood sugar levels.
  • Start your menstrual period. The hormonal changes may affect how insulin works.

You may have symptoms of low blood sugar if your blood sugar drops from a high level to a lower level. For example, if your blood sugar level has been higher than 300 mg/dL for a week or so and the level drops suddenly to 100 mg/dL, you may have symptoms of low blood sugar. However, if you have had diabetes for many years, you may not have symptoms of low blood sugar until your blood sugar level is very low.

Test Your Knowledge

Determine whether the following statements are true.

  1. Low blood sugar means that the level of sugar in the blood has dropped below what the body needs to function normally (usually below 70 mg/dL).

    1. True
    2. False
  2. A very low blood sugar level (below 20 mg/dL) is an emergency that requires immediate care.

    1. True
    2. False

Continue to Why? - Why the action is important? Why do I need to deal with low blood sugar emergencies?
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Author: Caroline Rea, RN, BS, MSLast Updated: August 14, 2007
Medical Review: Caroline S. Rhoads, MD - Internal Medicine
Matthew I. Kim, MD - Endocrinology & Metabolism

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