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How To Check Your Blood Sugar

Why do I need to check my blood sugar level?

High blood sugar levels increase your risk for heart attack, stroke, eye problems, and kidney problems. You can decrease your risk of these problems by controlling your blood sugar levels. Low blood sugar levels can also lead to serious health problems and must be treated right away. Check your blood sugar to help you learn how food, exercise, stress, and medicines affect your levels. Keep a record of your blood sugar levels. It can be used to adjust your meal plan, exercise routine, insulin doses, or diabetes medicine if needed.

How do I check my blood sugar level?

  • Check your blood sugar level with a glucose meter. This device uses a small drop of blood to measure your blood sugar level. Some glucose meters take the sample from your finger with a special lancet device. Other meters use blood from your thigh, forearm, or the palm of your hand.

  • Blood sugar levels change quickly after meals, after you take insulin, during exercise, and when you feel stressed or ill. It is best to use blood from your finger to check your blood sugar level during these times. Your healthcare provider will teach you how to use a glucose meter to check your blood sugar level. Ask your healthcare provider for more information about taking blood samples from areas other than your finger.

How do I choose a blood glucose meter?

There many different types of meters and test strips. Healthcare providers will help you choose the best meter for you. Ask yourself the following questions when you shop for a glucose meter:

  • Is the meter the right size for you?

  • Is it easy for you to see the numbers in the display area?

  • Does the meter seem easy to use?

  • Is it easy to get supplies for the meter if you are traveling?

  • Does the meter have a memory that keeps track of your blood sugar levels? Does the meter keep track of other details that you need?

What steps do I take to check my blood sugar level?

Read the instructions that came with your meter so that you understand how to use it. The following are general steps for testing your blood sugar level:

  • Wash your hands with soap and water.

  • Place a test strip into the blood glucose meter.

  • Choose a spot on the side of your fingertip and poke it with the lancet device. Wait for a drop of blood to form. If a drop does not form, gently squeeze your finger until a drop forms.

  • Place the drop of blood on or near the test area of the test strip. Wait until the right amount of blood has been drawn into the test strip.

  • Use gauze or a tissue to clean your fingertip. Keep it on the area until the bleeding has stopped.

  • Write down your blood sugar level.

  • Throw away the lancet in a hard container with a lid. Keep the container out of the reach of children and pets.

When and how often should I check my blood sugar level?

Ask your healthcare provider when and how often you should check your blood sugar levels. Check at least 3 times each day if you use an insulin pump or need several injections of insulin each day. Your healthcare provider may suggest that your blood sugar level should be between 70 mg/dL and 130 mg/dL before meals. Your blood sugar level may need to be less than 180 mg/dL after meals. Blood sugar levels need to be checked more often when you are sick, or if you change your daily routine. Test your blood sugar level if you feel like it may be too high (hyperglycemia) or too low (hypoglycemia).

What are the signs and symptoms of hyperglycemia?

Check your blood sugar level if you have any of the following signs and symptoms:

  • More thirst than usual

  • More urine than usual

  • More hunger than usual

  • Blurred vision

What are the signs and symptoms of hypoglycemia?

You need to eat some glucose right away if your blood sugar level is low. Ask your healthcare provider for more information about how to treat hypoglycemia. Check your blood sugar level if you have any of the following signs and symptoms:

  • Fast heartbeat

  • Feeling dizzy, lightheaded, shaky, or confused

  • Headache

  • Sweating

How do I keep a record of my blood sugar levels?

Write down your blood sugar level each time you test it. Write down the date, the time of the test (including if it was before or after a meal), and the result. Write down the time you took your insulin or diabetes pills. Record the type and amount of insulin or diabetes medicine you took. Write comments about anything that may have made your blood sugar level go up or down. Your blood sugar level can be affected by exercise, eating more or less than usual, or stress. Bring this record with you every time you see your healthcare provider.

How do I take care of my glucose meter and test strips?

  • Storage: Keep the test strips away from heat, cold, and moisture. Do not take a test strip out of the container until you are ready to use it. Put the lid back tightly on the container. Do not use test strips that are damaged, wet, or bent.

  • Expiration date: Check the date on the test strip container to be sure the test strips have not expired. Your blood sugar readings may be wrong if you use expired test strips. Use only the type of glucose test strips that work with your glucose meter.

  • Coding your meter: Your meter may need a special code that matches each new bottle of test strips you use. If your meter is not coded correctly, your blood sugar readings may be wrong. Follow the instructions for entering the code that came with your meter or strips.

  • Accuracy: Check the accuracy of your meter by testing a drop of control solution. Control solution often comes with a meter or can be bought at drug or medical supply stores. The blood sugar reading of the control solution should match the one that is listed on the bottle.

What are the risks of not testing my blood sugar level?

You may have low or high blood sugar levels and not have any symptoms. If you do not check your blood sugar levels, you will not know what your blood sugar levels are. Over time, high blood sugar levels can harm your heart, kidneys, eyes, blood vessels, and nerves. Low blood sugar levels can also lead to serious health problems and must be treated right away. Ask your healthcare provider for more information about low blood sugar levels and how to treat them.

When should I contact my healthcare provider?

  • You often have high or low blood sugar levels.

  • You have a fever.

  • You have questions or concerns about your condition or care.

When should I seek immediate care or call 911?

  • You are vomiting.

  • You cannot think clearly or are very weak, sweating, or pale.

  • You are breathing faster or slower than normal, are very sleepy, or your breath smells fruity.

  • You have chest pain.

  • You pass out.

  • You have a seizure.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© 2015 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or Truven Health Analytics.