Blood Glucose Monitoring, Adult

To manage your diabetes, you'll need to keep track of your blood sugar. This is called blood glucose monitoring.

• Know when to adjust your diabetes management plan with your health care provider.
• See how food, exercise, illness, and medicines affect your blood glucose.
• Know what your blood glucose is at any time.

• Before meals: 80–130 mg/dL (4.4–7.2 mmol/L).
• After meals: below 180 mg/dL (10 mmol/L).
• A1C level: less than 7%.

Supplies needed:

• Blood glucose meter.
• Test strips for your meter. Each brand of meter has its own strips. You must use the strips that came with your meter.
• A lancet. This is a sharp device used to poke your finger. Do not use a lancet more than once.
• A journal or logbook to write down your results.

How to check your blood glucose

Checking your blood glucose

1. Wash your hands with soap and water for at least 20 seconds.
2. Use the lancet to poke the side of your finger. Do not poke the tip of your finger. Also, try not to use the same finger each time.
3. Gently squeeze the finger until a small drop of blood appears.
4. Follow the meter instructions on how to insert the test strip, apply blood to the strip, and use the meter.
5. Write down your result and any notes.

Using different sites

Some blood glucose meters allow testing on other parts of your body to test your blood. The most common places are the forearm, thigh, upper arm, and palm of the hand. Check your meter's instructions.

Using different sites may not be as accurate as your fingers. If you think you have low blood glucose, only use your finger.

General tips

Blood glucose log

• Write down the result each time you check your blood glucose. Note anything that may be affecting your blood glucose. This can help you and your provider:
  • Look for patterns over time.
  • Adjust your management plan as needed.
• Check if your meter has an app or lets you download your records to a computer. Most meters keep a record of glucose readings in the meter.

If you have type 1 diabetes:

• Check your blood glucose as often as told. This may be:
  • Before each meal and snack.
  • Two hours after a meal.
  • Before bedtime.
  • If you have symptoms of hypoglycemia.
  • After treating your hypoglycemia.
  • Before doing things that have a risk of injury, such as driving or using machinery.
  • Before and after exercise.
  • Between 2:00 a.m. and 3:00 a.m.
• You may need to check your blood glucose more often, such as up to 6–10 times a day, if:
  • You have diabetes that is not well controlled.
  • You are ill.
  • You have a history of severe hypoglycemia.
  • You have hypoglycemia unawareness.

If you have type 2 diabetes:

• You may need to check your blood glucose 2 or more times a day. Check your blood glucose as often as told by your provider. This may include:
  • Before and after exercise.
  • Before doing things that have a risk of injury, such as driving or using machinery.
• You may need to check your blood glucose more often if:
  • Your medicine is being adjusted.
  • Your diabetes is not well controlled.
  • You are ill.

General tips

• Always have your blood glucose meter and supplies with you.
• After you use a few boxes of test strips, adjust your blood glucose meter as needed. Follow the meter instructions.
• If you have questions or need help, all blood glucose meters have a 24-hour hotline phone number that you can call. Also, contact your provider with any questions or concerns.

Where to find more information

• The American Diabetes Association: diabetes.org
• The Association of Diabetes Care & Education Specialists: diabeteseducator.org

Contact a health care provider if:

• Your blood glucose is at or above 240 mg/dL (13.3 mmol/L) for 2 days in a row.
• You have been sick or have had a fever for 2 days or longer and are not getting better.
• You have any of these problems for more than 6 hours:
  • You cannot eat or drink.
  • You have nausea or vomiting.
  • You have diarrhea.

Get help right away if:

• Your blood glucose is lower than 54 mg/dL (3 mmol/L).
• You become confused, or you have trouble thinking clearly.
• You have trouble breathing.
• You have moderate to high ketone levels in your pee.

• Do not wait to see if the symptoms will go away.
• Do not drive yourself to the hospital.