Getting the Most Out of Blood Glucose Meters

Keeping glucose levels under control can help people with diabetes feel better and also lower the risk of blindness, kidney disease, and nerve damage. Very high or very low blood sugar can have serious consequences.

Although blood glucose meters are fairly simple to operate, many things can go wrong if the user isn't careful. Here are some tips that can help people with diabetes get accurate results from their glucose meters.

• Be prepared before you do the test. Carefully read all instructions for your meter and test strips. Calibrate the meter or test it to be sure it's calibrated before you use it.

• Be sure that you're using test strips that are specified to work with your meter. Even if an incorrect test strip fits in your meter, it could give you the wrong results. Don't use test strips from a cracked or damaged bottle and don't use test strips that have passed their expiration date.

• Once you're ready to test, wash your hands, because even a little bit of food or sugar can affect the results. Make sure the drop of blood is the right size. Let the blood flow freely; don't squeeze your finger, since that can affect the results. Always use a whole test strip and insert it into the meter until you feel it stop against the end of the meter guide.

• Storage and maintenance are important, too. Be sure to keep your meter clean, and test it regularly with control solution. Have extra batteries charged and ready. Heat and humidity can damage test strips, so replace the bottle cap promptly after removing a strip. And store your meter and supplies according to manufacturer instructions.

What about glucose meters that allow you to use blood from places other than fingertips, such as the upper arm, forearm, base of the thumb, and thigh? This can give you more options. But blood from a finger stick shows changes in glucose levels more quickly than blood from other parts of the body. That means that glucose levels from these other places may not always be as accurate as readings from the fingertips, particularly when glucose levels are changing rapidly, including after a meal, after taking insulin, during exercise, or when you're ill or under stress. During these times, you should use blood from a finger stick. You should also use fingertip blood if you think your blood glucose is low, if you don't usually have symptoms when your blood glucose is low, or if the result from the alternative site doesn't match how you feel.

Glucose meters are generally reliable, but they're not as accurate as testing done in your doctor's office. So take your meter with you when you visit your doctor so you can compare it with your laboratory results. Finally, if your meter gives a normal reading but you still suspect your glucose is too low or too high, contact your doctor immediately.

Additional Information:

FDA Home Healthcare Committee. Home Healthcare Medical Devices: Blood Glucose Meters. September 2003.
http://www.fda.gov/cdrh/cdrhhhc/bgm.pdf

FDA Diabetes Information. Glucose Meters and Diabetes Management. June 14, 2005.
http://www.fda.gov/diabetes/glucose.html