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Checking Blood Glucose (Blood Sugar)


Checking your blood glucose (sometimes called your blood "sugar") is key to your health and to preventing problems that can result from having uncontrolled diabetes for many years. As uncomfortable and time-consuming as this may seem at the beginning, eventually it may become as routine as brushing your teeth. When you have diabetes, you need to test your blood glucose regularly at home to make sure it is within a healthy range and that your diabetes management plan is working. Keeping your blood glucose at or near normal can help prevent or delay serious complications, such as eye problems, kidney disease and nerve damage. By checking your blood glucose several times a day, you can adjust your diet, insulin or diabetes pills, or physical activity as needed to keep it under control.

Talk with your doctor and diabetes educator about how often you should check your blood glucose. As a rule, if you have type 1 diabetes, you may need to check your blood glucose three or four times a day. If you have type 2 diabetes, you may need to check two to four times a day.

If you are planning on any special or rigorous activity, it's important to be safe and check your blood glucose beforehand. Your blood sugar will drop more quickly during these activities and you may dip below a healthy level - which is called "hypoglycemia."

Check your blood glucose before:

  • driving
  • using heavy equipment
  • you have a hard or long workout or activity
  • travelling (don't forget to take your meter!)

Target Glucose Levels

Set your blood glucose level goals with your doctor and diabetes educator. Each person who has diabetes is different, and your goals may not be the same as someone else's. However, in general, most people with diabetes who self-test should have numbers that fall somewhere in this range:

  • Before meals: 90 to 130 mg/dL
  • one to two hours after meals: less than 180 mg/dl

When you set up your diabetes treatment plan with your doctor, ask what your blood glucose goals should be. Write them down so that you can refer to them as you do your self-testing.

Use a Blood Glucose Meter

You need a special glucose monitor, sometimes called a "meter," that is designed for home use in checking blood glucose. Many meters are small and lightweight, so you can take them wherever you go. Talk with your diabetes educator about the models that will best fit your lifestyle.

In addition to the meter, you'll need special test strips made just for the meter you purchase. Plus you'll need alcohol to clean your fingertips, and lancets to prick your fingertips so that you can get a drop of blood.

Keep a Record

Always write down the results of each blood glucose test in a record book or diary. Some blood glucose meters come with a diary you can use. Make sure you regularly record the following:

  • the date you did the test
  • time of day
  • your glucose reading
  • doses of any medicines you're taking and when you took them
  • any notes on special eating experiences or unusual foods you ate

Bring your blood glucose diary with you when you meet with your doctor or other members of your diabetes management team. This information can help you and your doctor and other team members determine if your management plan needs to be changed to fit your needs.You can buy a meter and the supplies to use it from your local pharmacy or from diabetes supply companies. (Note that the cost of blood glucose meters may be covered by your health insurance. Be sure to ask.)


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