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Diabetes: Checking Your Blood Sugar
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.
How to test your blood sugar
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.
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 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:
- Wash your hands with warm, soapy water, and dry them well with a clean towel.
- 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.
- 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.
- Get your blood sugar meter ready. Follow the manufacturer's instructions for your specific meter.
- 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.
- Put a drop of blood on the correct spot of the test strip, covering the test area well.
- Using a clean cotton ball, stop the bleeding by applying pressure to the place you stuck.
- 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 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.
Current as of: April 16, 2019
Author: Healthwise Staff
Medical Review:E. Gregory Thompson, MD - Internal Medicine & Adam Husney, MD - Family Medicine & Kathleen Romito, MD - Family Medicine & Rhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator
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