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Diabetes: Dealing With Low Blood Sugar From Medicines

Introduction

Low blood sugar (hypoglycemia) occurs when the sugar (glucose) level in the blood drops below what the body needs to function normally. Some pills for diabetes can cause low blood sugar.

Even mild low blood sugar can affect the way you think and respond to things around you. And mild low blood sugar can quickly drop to a more dangerous level.

Click here to view an Actionset.Diabetes: Dealing With Low Blood Sugar From Insulin
  • Low blood sugar as a side effect of oral diabetes medicines usually causes mild symptoms, such as sweating, shakiness, and hunger.
  • Taking too many of your diabetes pills in one day, not eating enough food, or doing strenuous physical activity can cause your blood sugar level to drop below your target range.
  • If your blood sugar is low and you don't eat anything, it may drop to a very low level. Keep some hard candy, raisins, or other quick sugar foods with you at all times. Eat some at the first sign of low blood sugar.
  • Test your blood sugar often so you do not have to guess when it is low.
  • Teach your friends and coworkers what to do if your blood sugar is very low.
 

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 usually develop quickly.

  • If your blood sugar level drops just slightly below your target range, you may have symptoms of mild low blood sugar. If you eat something that contains sugar, your symptoms may last only a short time. If you have had diabetes for many years, you may not realize your blood sugar is low until it drops very low. 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 start. You may become too weak or confused to eat something to raise your blood sugar level.
  • If your blood sugar level drops very low (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.

What causes low blood sugar?

Low blood sugar levels can be caused by having too much insulin in your body and/or not enough sugar in your blood. This can happen with some oral medicines used to treat diabetes and also with insulin shots. This is more likely to happen if you eat less food than usual, exercise, or do intense physical work. Very low blood sugar levels most often develop rapidly (in 10 to 15 minutes) when a person has skipped a meal and is doing intense physical work. Reduced kidney function can prolong the action of diabetes medicine, possibly making low blood sugar levels more frequent.

Usually, blood sugar levels in people who take diabetes medicine drop only low enough to cause mild symptoms. Very low blood sugar levels usually do not occur in people with diabetes who do not take insulin shots. Some pills used to treat type 2 diabetes are more likely to cause low blood sugar than others.

Low blood sugar levels can occur if you:

  • Take too many of your sulfonylurea pills or meglitinide pills in a day or take your doses too close together.
  • Continue to take your full dose of sulfonylurea pills or meglitinide pills when you are not going to eat your usual amount of food.
  • Exercise strenuously without eating enough food.
  • Drink too much alcohol, especially on an empty stomach.
  • Take certain other medicines that lower blood sugar. Some medicines that you can buy without a prescription can affect blood sugar. Talk with your doctor about your prescription and nonprescription medicines and the risk of developing very low blood sugar levels.

Test Your Knowledge

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.

  • True
    This answer is correct.

    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. When your blood sugar level drops below 70 mg/dL, you most likely will have symptoms, such as feeling tired, weak, or shaky.

  • False
    This answer is incorrect.

    Low blood sugar does mean that the level of sugar in the blood has dropped below what the body needs to function normally, usually below 70 mg/dL. When your blood sugar level drops below 70 mg/dL, you most likely will have symptoms, such as feeling tired, weak, or shaky.

  •  

Very low blood sugar levels (below 20 mg/dL) are emergency situations and require immediate care.

  • True
    This answer is correct.

    Very low blood sugar levels (below 20 mg/dL) are emergencies, and you need care immediately. If you do not receive immediate care, a very low blood sugar level can lead to coma and death.

  • False
    This answer is incorrect.

    Very low blood sugar levels (below 20 mg/dL) are emergencies, and you need care immediately. If you do not receive immediate care, a very low blood sugar level can lead to coma and death.

  •  

Continue to Why?

 

Even mild low blood sugar can affect the way you think and respond to things around you. And mild low blood sugar can quickly drop to a more dangerous level.

If your blood sugar drops below 40 mg/dL, your brain may receive too little sugar to work properly and your judgment and muscle coordination will be affected. These are symptoms of moderate low blood sugar. You may not realize that your blood sugar is too low, and you may not be aware that you need to eat food to raise the level. Someone else may have to help you eat or drink something to raise your blood sugar level. If you do not get help, your brain may not work properly. This can cause an accident if you are driving a car or operating other machinery.

If your blood sugar level drops below 20 mg/dL, which is considered severe low blood sugar, you can lose consciousness. If you do not receive prompt emergency care, you may go into a coma, have a seizure, heart attack, or stroke, and possibly die.

Test Your Knowledge

If my blood sugar level drops very low (below 20 mg/dL):

  • I can fall into a coma and possibly die.
    This answer is correct.

    If your blood sugar level drops to 20 mg/dL or lower, you can fall into a coma and possibly die.

  • I will act like I am okay.
    This answer is incorrect.

    You won't act like you're okay. If your blood sugar level drops to 20 mg/dL or lower, you can fall into a coma and possibly die.

  • I will be able to eat or drink something to raise it.
    This answer is incorrect.

    If your blood sugar level drops to 20 mg/dL or lower, someone else will need to help you eat or drink something to increase your blood sugar level, or you may need emergency medical help. You may fall into a coma and possibly die.

  • I can still function if I need to.
    This answer is incorrect.

    If your blood sugar level drops to 20 mg/dL or lower, you won't be able to function. You may fall into a coma and possibly die.

  •  

Continue to How?

 

Here are some ways you can manage low blood sugar.

Be prepared

  • Keep some quick-sugar foods with you at all times. These foods will help raise your blood sugar by about 30 mg/dL within about 15 minutes. If you are at home, you most likely will already have something close at hand that contains sugar, such as table sugar or fruit juice. Carry some hard candy or glucose tablets when you are away from home.
  • Know the symptoms of low blood sugar, such as sweating, blurred vision, and confusion. Post them where you will see the list often. And carry a copy in your wallet or purse. Be sure that your partner and others concerned know your early symptoms, including the signs of low blood sugar at night.
  • Wear medical identification, such as a medical alert bracelet, to let people know that you have diabetes. People will know that you have diabetes and will get help for you if needed.
  • Teach others (at work and at home) how to check your blood sugar in case you cannot check it yourself. Keep the instructions for using your blood sugar (glucose) meter with the meter, so the person can review the instructions if needed.
  • Teach other people (at work and at home) what to do in case your blood sugar becomes very low. Post information on emergency care for low blood sugar in a convenient place so that those around you can take the proper steps when your blood sugar is very low.
  • Take precautions when you are driving and do not drive if your blood sugar is below 70 milligrams per deciliter (mg/dL).

Treat low blood sugar early

Treat low blood sugar levels as soon as you (or someone else) notice the symptoms:

  • Check your blood sugar often. If you have had diabetes for many years, you may not have symptoms until your blood sugar is very low.
  • Follow the steps for dealing with low blood sugar when you first develop your symptoms of low blood sugar or when your blood sugar level is below your target range (usually below 70 mg/dL). Encourage others to tell you if they notice you are developing signs of low blood sugar.
  • Keep a record (What is a PDF document?) of low blood sugar levels. Write down your symptoms and how you treated your low blood sugar.
  • Notify your doctor if you are having frequent low blood sugar problems. Your pills for diabetes may need to be adjusted or changed.

Test Your Knowledge

To be prepared for low blood sugar, I need to carry:

  • My pills for diabetes.
    This answer is incorrect.

    Your pills won't help if you have low blood sugar. To be prepared for low blood sugar, always have some quick-sugar foods with you. Review the list of quick-sugar foods.

  • Some quick-sugar foods.
    This answer is correct.

    To be prepared for low blood sugar, always have some quick-sugar foods with you. Review the list of quick-sugar foods.

  •  

To treat low blood sugar before it becomes an emergency, I need to:

  • Take an extra pill for diabetes.
    This answer is incorrect.

    An extra dose of your medicine will cause your blood sugar to drop even lower. The best way to deal with low blood sugar emergencies is to prevent them by treating low blood sugar symptoms as soon as you (or someone else) notice the symptoms. To raise your blood sugar, eat some food that contains sugar.

  • Go to sleep and rest.
    This answer is incorrect.

    If you sleep or rest, your blood sugar level may continue to drop, leading to an emergency situation. The best way to deal with low blood sugar emergencies is to prevent them by treating low blood sugar symptoms as soon as you (or someone else) notice the symptoms. To raise your blood sugar, eat some food that contains sugar.

  • Eat some food that contains sugar.
    This answer is correct.

    To treat low blood sugar before it becomes an emergency, you need to eat some food that contains sugar. Food that contains sugar will raise your blood sugar level and prevent an emergency.

  •  

Continue to Where?

 

Now that you have read this information, you are ready to start dealing with low blood sugar levels effectively.

If you have questions about this information, take it with you when you visit your doctor. You may want to write down any questions you have.

If you would like more information on dealing with low blood sugar levels, the following resources are available:

Organization

American Diabetes Association (ADA)
1701 North Beauregard Street
Alexandria, VA  22311
Phone: 1-800-DIABETES (1-800-342-2383)
Email: AskADA@diabetes.org
Web Address: www.diabetes.org
 

The American Diabetes Association (ADA) is a national organization for health professionals and consumers. Almost every state has a local office. ADA sets the standards for the care of people with diabetes. Its focus is on research for the prevention and treatment of all types of diabetes. ADA provides patient and professional education mainly through its publications, which include the monthly magazine Diabetes Forecast, books, brochures, cookbooks and meal planning guides, and pamphlets. ADA also provides information for parents about caring for a child with diabetes.


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References

Other Works Consulted

  • American Diabetes Association (2013). Standards of medical care in diabetes—2013. Diabetes Care, 36(Suppl 1): S11–S66.

Credits

By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer Jennifer Hone, MD - Endocrinology, Diabetes and Metabolism
Last Revised June 29, 2011

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