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Diabetes: Checking Your Blood Sugar

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Testing your blood sugar can help you manage your diabetes, especially if you're having trouble controlling your levels. It helps you see if your levels are in your target range. And it may help you avoid blood sugar emergencies.

Having a record of your blood sugar over time can help you and your doctor know how well your treatment is working and whether you need to make any changes.

But those aren't the only benefits of testing. It can also help you know what things in your daily life affect your blood sugar levels. Keeping a log of your blood sugar levels, your meals, your medicine, and any activity might make it easier to see the connections.

When should you test your blood sugar?

Some people who have diabetes test their blood sugar rarely or not at all. Other people—such as people who use insulin—test it often.

Talk to your doctor or diabetes educator about testing your blood sugar. Together you can decide how often and when you should check your numbers.

How to test your blood sugar

Do the test

Figure 1

Gather your supplies.

Gather the things you need to test your blood sugar. This usually includes the meter, needle (lancet) and lancet holder, test strips, and cotton balls.

Figure 2

Learn how to use the equipment.

Read the information from the manufacturer and your doctor to be sure you know how to use the blood sugar meter, lancet holder, and test strips.

Figure 3

Check the expiration date.
Expiration date on test strip bottle.

Check the expiration date on your test strips. If you use expired test strips, your test results might not be accurate.

Figure 4

Match the code numbers.

Many meters don't need a code from the test strips, but some will. If your meter does, make sure the code number on the bottle of test strips matches the number on your meter. If the numbers don't match, follow the directions that come with your meter for changing the code number.

Figure 5

Wash your hands.

Wash your hands with warm, soapy water, and dry them well with a clean towel.

Figure 6

Put a clean needle (lancet) in the lancet holder.

The lancet holder is about the size of a pen. It holds the lancet in place and controls how deeply the lancet goes into your skin.

Figure 7

Get the test strip ready.

Take one strip from the bottle of test strips. Follow the directions to prepare your meter to receive the blood sample. Don't forget to put the lid back on the bottle right after removing the strip.

Figure 8

Prick your finger.

Use a lancet holder to prick the side of your fingertip with the lancet. You can use a lancet without a holder, but a holder makes it easier to use. You can prick any finger.

Figure 9

Test a small sample of your blood.

Touch the drop of blood with the correct spot of the test strip. Be sure to get enough blood to cover the test area on the strip.

Figure 10

Stop any bleeding.

If your finger continues to bleed, use a clean cotton ball to apply pressure to your fingertip to stop the bleeding.

Figure 11

Record your results.
Blood sugar log, with columns for date, time, blood sugar level, and notes.

Wait for the results. Most meters take only a few seconds to give you the results. It's important to record your blood sugar results and when you tested it. It's also helpful to note when you last had something to eat. Your doctor will use your record to see how often your blood sugar levels are in your target range.

Record the results

You and your doctor will use your blood sugar testing record to see how often your levels are in your target range. Here are some ideas for how to do it.

Prevent sore fingers

Frequent blood sugar testing can lead to sore fingertips. Here are some ideas to help avoid this.

Credits for Diabetes: Checking Your Blood Sugar

Current as of: February 28, 2023

Author: Healthwise Staff
Clinical Review Board: All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

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