Monitoring Blood Glucose

The doctor or health care provider wants you to measure how much glucose, a type of sugar, is in your blood. It is often called blood sugar. For the body to have the energy to work right, blood glucose needs to be balanced. Too much glucose, called hyperglycemia, can cause harm to the body over time. Too little, called hypoglycemia can cause a person to get very sick, very fast. When hypoglycemia happens, it must be treated right away.

The more often blood glucose is tested, the better you will know how to keep it balanced.

When to Test Blood Glucose

  • Your child’s doctor or health care provider will tell you how often and at what times to check their blood glucose.
    • You may need to test blood glucose 2 to 4 or more times a day.
    • The number of times to check may change over time.

Supplies You Will Need

  • Blood glucose monitor (meter or machine)
  • Alcohol swabs or soap and water
  • Lancets (sharp-pointed object to prick the skin)
  • Test strips
  • Spring-loaded lancet device
  • Band-Aid® (optional)
  • Tissue, cotton balls, or paper towel
  • A container with a lid, like a laundry detergent bottle or a sharps container, to safely throw away used supplies
  • Blood glucose log or a book to write down the reading (blood glucose number)

About Test Strips

  • Test strips are good until the manufacturer’s expiration date or for 6 months after the bottle is opened, whichever comes first.
  • Check the expiration date before buying the strips. Don’t buy or use test strips that do not have an expiration date or are expired.
  • Write the date on the bottle after you open it.
  • Throw away test strips that are damaged. To prevent damage, store test strips away from heat, direct light, or moisture.



  • Store strips away from light like in a drawer.
  • Store at room temperature, not over 86° Fahrenheit (F) or 30° Celsius (C) and in a dry place.
  • Keep strips in their original bottle.
  • Close cap tightly to protect strips from falling out of bottle, moisture, or heat.
  • Store all testing supplies out of the reach of children and pets.
  • Do not store strips in direct sunlight, a car, or a bathroom.
  • Do not refrigerate.
  • Do not put strips in a different bottle.
  • Do not keep the cap off.
  • Do not put testing supplies where children or pets can get to them.

How to Check Blood Glucose

1. Set up your supplies on a clean surface where they’re easy to reach. Blood glucose meter with test strip inserted

2. Have your child wash their hands with soap and water and dry them. Or clean the finger that will be used for the test with an alcohol swab. Let it air dry.

  • Don’t use hand sanitizers, gel sprays, or alcohol foam.
  • If the fingers are cold, warm them up by holding them under running warm (not hot) tap water. Dry the fingers. It is harder to get blood from cold fingers.

3. Load the lancet into the lancet device. Twist off the lancet’s cap. Put the device’s cap back on. Push the test strip all the way into the blood glucose meter (Picture 1).

4. Select a place on the side of a finger to do the test (Picture 2).

  • Choose a site near the fingertip. Do not prick the center of the finger or the very tip (Picture 2).
  • Do not use the thumb for the test.
  • Do not prick skin in a place that is not healed or is sore.
  • Use a different finger and site each time. This will prevent scar tissue (a callous) from forming at a site. A callous can make it harder and more painful to get blood from that place.

5. Hold the test finger still. Press the lancet device firmly on the side of the fingertip. Push the device’s trigger button. The lancet will prick the finger. Prick the side of the finger with the lancet

6. You should see a drop of blood right away. If you used an alcohol pad, wipe off the first drop of blood with a clean tissue or cotton ball.

7. If the drop of blood is not big enough for the test, gently squeeze and release the fingertip. To help the blood flow, point the finger down towards the floor when squeezing.

8. When the glucose monitor prompts you, touch the end of the strip with the drop of blood. The strip will suck up the blood.

9. Wipe the finger with a clean tissue or cotton ball. If needed, put on a Band-Aid.

10. Write down the blood glucose reading in the log or record book.

11. Throw away dirty supplies. Lancets should only be used 1 time. Safely throw them away in a plastic detergent bottle or sharps container.


  • Your child’s doctor or health care provider may ask you to send your child’s blood glucose logs to them. For families seen at Nationwide Children’s Hospital, send the logs to:
  • Bring your glucose meter and blood glucose logs to all medical appointments.

Monitoring Blood Glucose (PDF,) Arabic (PDF,) Nepali (PDF,) Somali (PDF,) Spanish (PDF)

HH-I-22  ©2008, revised 2022, Nationwide Children’s Hospital

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