Skip to Content

Health Library

  • Diabetes: Checking Your Blood Sugar

Diabetes: Checking Your Blood Sugar

Introduction

Because you have diabetes, you need to know when your blood sugar level is outside the target range for your body. Fortunately, you can see what your blood sugar level is anywhere and anytime by using a home blood sugar meter (blood glucose meter). Using the meter, you can find out what your blood sugar level is quickly.

Knowing your blood sugar level helps you treat low or high blood sugar before it becomes an emergency. It also helps you know how exercise and food affect your blood sugar and how much short-acting insulin (if you take insulin) to take. Most importantly, it helps you feel more in control as you manage life with diabetes.

Three keys to success in monitoring your blood sugar anywhere are:

  • Keeping your meter and supplies with you at all times so that you always have them when you need them.
  • Making it a habit to check your blood sugar level by building it into your routine.
  • Checking your blood sugar meter's accuracy when you visit your doctor by comparing your results with your doctor's results.
 

Your doctor will most likely take a sample of blood from a vein to test your blood sugar level in his or her office or lab every 3 to 6 months. The blood sample is used to:

  • Check your blood sugar level at the time of the test (blood glucose test).
  • Measure how well your blood sugar has stayed within your target range over the past 2 to 3 months (A1c test).

You may not get the results from these tests for a few hours or even a few days.

Because you have diabetes, you need to know what your blood sugar level is every day. You can check your blood sugar level anytime and anywhere by using a home blood sugar meter. This is often referred to as home blood sugar monitoring or self-testing. Your doctor may want you to check your blood sugar level several times a day, especially if you take insulin.

To test your blood sugar level using a blood sugar meter, prick the side of your fingertip with a small needle (lancet) to collect a drop of blood. Some blood sugar meters allow you to prick other sites on your body, such as your forearm, leg, or hand. Place the drop of blood on a test strip inserted into your meter. The meter shows the results of your test.

Test Your Knowledge

Home blood sugar monitoring involves:

Continue to Why?

 

Monitoring your blood sugar level takes the guesswork out of your daily diabetes care. Testing your blood sugar at home helps you know:

  • When your blood sugar is low. Low blood sugar can lead to an emergency. If your blood sugar drops just below the level that is safe for your body and you quickly eat something containing sugar, your blood sugar will rise and you may prevent an emergency.
  • When your blood sugar is high. Over time, high blood sugar levels cause permanent damage to the eyes, heart, kidneys, blood vessels, and nerves. If you are pregnant, high blood sugar levels may cause problems for you and your baby.
  • What your blood sugar level is before a meal. If you take short-acting insulin, you can use these results to determine how much insulin to take.
  • How different types of food affect your blood sugar.
  • How exercise affects your blood sugar. Exercise usually lowers your blood sugar level.
  • What your blood sugar is when you are ill. Severe illness or stress usually causes higher blood sugar levels.
  • When your medicine for diabetes may need to be adjusted. If your blood sugar levels remain high over a period of time or you have frequent low blood sugar, your medicine for diabetes may need adjusting. Talk to your doctor about this.

Test Your Knowledge

Home blood sugar monitoring helps you know how exercise has affected your blood sugar.

  • True
    This answer is correct.

    Home blood sugar monitoring helps you know how exercise has affected your blood sugar. This monitoring helps you know what your blood sugar level is at the time of the testing. Checking your blood sugar after exercising will help you know whether your blood sugar levels are staying within a target range.

  • False
    This answer is incorrect.

    Home blood sugar monitoring does help you know how exercise has affected your blood sugar. This monitoring helps you know what your blood sugar level is at the time of the testing. Checking your blood sugar after exercising will help you know whether your blood sugar levels are staying within a target range.

  •  

Continue to How?

 

Monitoring your blood sugar level at home takes the guesswork out of your daily diabetes care. You will know what your blood sugar level is at the time of testing. Here is a simple way to get started.

Get organized

Before you start testing your blood sugar:

  • Talk with your doctor about how often and when you should test your blood sugar. Record your blood sugar testing timesblood sugar testing times(What is a PDF document?).
  • Link testing your blood sugar with other daily activities, such as preparing breakfast or before your afternoon walk. This will help you establish the habit of self-testing.
  • Gather the supplies to test your blood sugar. Keep your supplies together so that you can do a test quickly if needed.
  • Check your equipment before you do each test.
    • Check the expiration date on your testing strips. If you use expired test strips, you may not get accurate results.
    • Many meters don't need a code from the test strips, but some will. If your meter does, make sure the code numbers on the testing strips bottle match the numbers on your meter. If the numbers do not match, follow the directions that come with your meter for changing the code numbers.
  • Most manufacturers recommend using the sugar control solution that is made by your meter's manufacturer the first time you use a meter, when you open a new bottle of test strips, or to check the accuracy of your meter's results. Follow the directions that came with your meter for using the control solution properly.
  • At regular intervals, properly care for your equipment. Put a copy of the care of blood sugar supplies with your bag or kit as a reminder.

Do the test

Some people who have diabetes test their blood sugar rarely or not at all. Other people—such as pregnant women or people who use insulin—test it often. The more often you test your blood sugar, the more you will know about how well your treatment is keeping your blood sugar levels within a target range.

Follow these steps when testing your blood sugar:

  1. Wash your hands with warm, soapy water, and dry them well with a clean towel.
  2. Put a clean needle (lancet) in the lancet device. The lancet device is a pen-sized holder for the lancet. It holds and positions the lancet and controls how deeply the lancet goes into your skin.
  3. Get a test strip from your bottle of testing strips. Put the lid back on the bottle immediately to prevent moisture from affecting the other strips.
  4. Get your blood sugar meter ready. Follow the manufacturer's instructions for your specific meter.
  5. Use the lancet device to stick the side of your fingertip with the lancet. Some devices and blood sugar meters allow blood testing on other parts of the body, such as the forearm, leg, or hand. Be sure you know where your device can be used.
  6. Put a drop of blood on the correct spot of the test strip, covering the test area well.
  7. Using a clean cotton ball, stop the bleeding by applying pressure to the place you stuck.
  8. Wait for the results. Most meters take only a few seconds to give you the results.

Record the results

Recording your blood sugar results is very important. You and your doctor will use your record to see how often your blood sugar levels are in your target range. This information lets you and your doctor know how your medicine, food, and activity are affecting your blood sugar. Be sure to take your record with you on each visit to your doctor or diabetes educator.

To record your results, you can:

  • Get printed blood sugar logs from companies that make diabetic medicines and supplies. Or use a home blood sugar diaryhome blood sugar diary(What is a PDF document?).
  • Make a blood sugar log in a notebook. You can record other information in the log or notebook, such as insulin doses, your exercise, and food you have eaten. You and your doctor will find this information most useful when looking for patterns and reasons for your blood sugar levels.
  • Use the memory storage feature of your meter and other note-taking features. Find out if your doctor can transfer the data to your medical record or if you can make reports to share.

Preventing sore fingers

The more often you test your blood sugar, the more likely you are to have sore fingertips. These suggestions can help prevent sore fingers:

  • Do not prick the tip of your finger. If you do, the prick is more painful and you may not get enough blood to get accurate results. Always prick the side of your fingertip. Also, do not prick your toes to get a blood sample. This can increase your risk of developing a dangerous infection in your foot.
  • Don't squeeze your fingertip. If you have trouble getting a drop of blood large enough to cover the test area of the strip, hang your hand down below your waist and count to 5. Then squeeze your finger beginning closest to your hand and moving outward to the end of your finger.
  • Use a different finger each time. Establish a pattern for which finger you stick so that you will not use some fingers more than others. If a finger becomes sore, avoid using it to test your blood sugar for a few days.
  • Use a different device. Some blood sugar meters need smaller drops of blood. Some blood sugar meters can use sites other than the fingers, such as the forearm, leg, or hand.
  • Use a different lancet. Some lancet devices can be set to prick your skin deeply or lightly depending on the thickness of your skin and where on your body you are getting the blood.
  • Do not reuse the lancet. It can get dull and cause pain. A used lancet can carry bacteria that can make you sick. Some people reuse lancets anyway. If you do, wash your hands well each time you use it. And use a new one each day to reduce the chance for bacteria growth.

Test Your Knowledge

To test your blood sugar, put a drop of blood on the test strip used with your home blood sugar meter.

  • True
    This answer is correct.

    To test your blood sugar at home, you put a drop of blood on a test strip inserted in the meter. The meter provides the results of your blood sugar test.

  • False
    This answer is incorrect.

    To test your blood sugar at home, you do need to put a drop of blood on a test strip inserted in the meter. The meter provides the results of your blood sugar test.

  •  

Continue to Where?

 

Now that you have read this information, you are ready to start monitoring your blood sugar levels at home.

Talk with your doctor

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

If you haven't talked with your doctor about when and how often to test your blood sugar, do so during your next visit. Make sure to record the times you need to check your blood sugar each day and when you are stressed or ill.

If you would like more information on blood sugar monitoring, 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.


Credits

By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer Rhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator
Last Revised August 12, 2013

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.

© 1995-2013 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

Decision Points

Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.

You'll find Decision Points to help you answer questions about:

Interactive Tools

Get started learning more about your health!

Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.

Symptom Checker

Feeling under the weather?

Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.

Connect With CentraCare