How to Test Your Blood Sugar

Medically Reviewed by Brunilda Nazario, MD on July 21, 2016
From the WebMD Archives

When you're diagnosed with type 2 diabetes, your health care provider may ask you to test your blood sugar levels, especially if you need daily insulin injections. "When you're on insulin, there's a risk of low blood sugar, which can be very dangerous," says Cara Harris, a certified diabetes educator for The Ohio State University Diabetes and Metabolism Research Center. Regular blood tests allow you to spot trends or problems, and alert your doctor or other provider to change your medication if needed, she adds.

To check your blood sugar, you'll use a glucometer, a device that pricks your finger, giving you a tiny blood sample to test. "Most glucometers are pretty similar nowadays," Harris says, but she notes that some brands offer different features, such as the ability to test on areas of your body other than your fingers, or a way to record information about what you ate. If you need help choosing a meter, ask your diabetes educator, Harris says. Before you choose, she recommends checking with your insurance company; some insurers only cover certain models.

Many health care providers say you should check your blood sugar 2 to 4 times a day. Before you test, clean your skin with soap and water. "Sometimes patients will peel an orange and then test without washing their hands first, and it can alter the results," Harris says. If you don't have soap and water nearby, you can use hand sanitizer, but allow it to dry before testing.

Each time you check your blood sugar, record your results. This lets you review your numbers with your doctor or diabetes educator and spot any trends. "It's not so much the checking that's important, but what you do with the results," Harris stresses. "Be sure to talk with your provider about what those numbers mean." If your levels are too high or too low, it could be the result of your food choices, exercise, or medications, she says. Adjusting your routine may help you bring your numbers back into target range, usually between 80 and 130 mg/dL. (Your target may differ, depending on things like your age, Harris notes.)

While some glucometers record test data, Harris recommends writing the information in a logbook or entering it in an app, which makes it easier to review and see potential problems. Harris says some of her patients have used apps such as Glucose Buddy and mySugr. Both are free on Android and Apple devices.

At your next appointment, ask your diabetes educator:

  • What blood sugar target range should I aim for?
  • If I stop testing my blood sugar, what will happen?
  • Can I send you my blood sugar logbook to review?
  • Can you recommend any apps or websites to record my blood sugar levels?

Show Sources


Cara Harris, nurse practitioner and certified diabetes educator, Ohio State University Hospital East.

Mayo Clinic: "Blood sugar testing: Why, when and how."

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