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How and When to Test Your Blood Sugar With Diabetes

Most people with diabetes need to check their blood sugar (glucose) levels regularly. The results help you and your doctor manage those levels, which helps you avoid diabetes complications.

There are several ways to test your blood sugar:

From Your Fingertip: You prick your finger with a small, sharp needle (called a lancet) and put a drop of blood on a test strip. Then you put the test strip into a meter that shows your blood sugar level. You get results in less than 15 seconds and can store this information for future use. Some meters can tell you your average blood sugar level over a period of time and show you charts and graphs of your past test results. You can get blood sugar meters and strips at your local pharmacy.

Meters That Test Other Sites: Newer meters let you test sites other than your fingertip, such as your upper arm, forearm, base of the thumb, and thigh. You may get different results than from your fingertip. Blood sugar levels in the fingertips show changes more quickly than those in other testing sites. This is especially true when your blood sugar is rapidly changing, like after a meal or after exercise. If you are checking your sugar when you have symptoms of hypoglycemia, you should use your fingertip if possible, because these readings will be more accurate.

Continuous Glucose Monitoring System: These devices, also called interstitial glucose measuring devices, are combined with insulin pumps. They are similar to finger-stick glucose results and can show patterns and trends in your results over time.

When Should I Test My Blood Sugar?

You may need to check your blood sugar several times a day, such as before meals or exercise, at bedtime, before driving, and when you think your blood sugar levels are low.

Everyone is different, so ask your doctor when and how often you should check your blood sugar. If you're sick, you'll probably need to test your blood sugar more often.

What Affects Your Results

If you have certain conditions, like anemia or gout, or if it's hot or humid or you're at a high altitude, that can affect your blood sugar levels.

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