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What are the guidelines for blood glucose monitoring?

Edited: 18.04.2024

Anne-Charlotte Ficheroulle

Pharmacist, Digital Innovation Manager, A4D

1. What are the tools you need for blood glucose monitoring?

Blood glucose meter
It is a portable electronic device that is used to measure how much glucose is in your blood. It only needs a small drop of blood from your finger. The blood glucose meter should be maintained according to the manufacturer’s advice and calibrated regularly. Procedures may vary from one device to another. Check the users guide or ask your doctor/nurse how to use and store the blood glucose meter.

Blood glucose test strips
Use only test strips designed for your meter. You can only use a test strip once. That means you’ll have to take out a new one every time you want to check your blood glucose levels. Do not use expired test strips. Store test strips as directed. Do not place test strips in the refrigerator.

Finger prickers and lancets
A lancet is a fine, sharply pointed needle used to prick the skin. You will need a finger pricker, with a lancet attached, to obtain the drop of blood needed for the blood glucose test.

Read more.

2. When and how often do I need to check my blood glucose levels?

You should test your blood glucose levels at least 4 times per day but aim for 6 times if you have enough test strips available and keep a record of the result.

Blood glucose is best measured:
1. When you wake up, before breakfast
2. In the late morning before you eat lunch
3. In the evening before you eat dinner
4. Before you go to sleep

When it’s possible and if you have enough test strips, you can add an extra test:
5. 2.5 hours after eating breakfast
6. 2.5 hours after eating lunch

You may test more often when you are doing vigorous exercise (before, during, and several hours after), sometimes during the night to detect nocturnal low or high blood glucose level, or when you are sick to prevent hyperglycaemic crises. It’s also important to test to confirm hypoglycaemia (low blood glucose level) and to monitor recovery.

Out-of-control blood glucose levels not only lead to short-term problems like hypoglycaemia but also life-threatening events like diabetic ketoacidosis (DKA) and diabetic coma.

3. The importance of blood glucose monitoring

Successful diabetes management requires regular blood glucose monitoring. You can aim for 6 times per day, if you have enough test strips available. The results should be regularly reviewed with your doctor to identify your glucose fluctuation pattern. With this knowledge, your doctor will be able to adjust your diabetes treatment plan.

Of course, it’s not always easy to have 6 test strips available with you everyday. If you have less, try at least to test 4 times per day before meals and before bedtime and you can always discuss this with your doctor.

4. How to check blood glucose levels?

1. Wash and dry your hands
2. Insert the test strip in the blood glucose meter
3. Prick your finger with the lancet
4. Apply the drop of blood to the test strip until it has absorbed enough blood to begin the test
5. Within seconds, the blood glucose meter will give you a result
6. Record the result in your blood glucose diary or logbook
7. Discard the used test strip and lancet properly. Store the blood glucose meter.

Tips: Choose your spot—don’t check from the same finger all the time. Using the side of the fingertip may be less painful than the pads.

5. How to read the results?

A good blood glucose level is between 4 – 10 mmol/l (72 – 180 mg/dL).

  • When you wake and before meals aim for a level between 4 – 7 mmol/L (72 – 126mg/dL)

  • After meal and at bedtime aim for a level between 5 – 10 mmol/L (90 – 180 mg/dL)

Your target level will be individual to you. Please discuss with your doctor what your range should be.

If the reading is below 4.0 mmol/L (72 mg/dL), treat as a HYPO (low blood glucose level). Refer to the hypoglycaemia fact sheet for details.

Sometimes you may experience hypoglycaemia symptoms at a level over or around 4.0 mmol/L (72 mg/dL) – they should still be treated for a HYPO.

Please note that:

  • If your pre-meal blood glucose is always high, your preceding dose of insulin may have been too low.

  • If your pre-meal blood glucose is always low, your preceding dose of insulin may have been too high.

  • If your pre-meal blood glucose is sometimes high and sometimes low, there could be lots of reasons like insulin dose, food that you eat and exercise.

So you should discuss this with your doctor.

6. What is HbA1c?

Every 3 months your doctor will do a HbA1c test. The result of this test reflects your average blood glucose level for the past two to three months. The higher your HbA1c level is, the poorer your blood glucose control and the higher your risk of diabetes complications.

With a good blood glucose self-monitoring habit, your doctor will target a HbA1c result below 7%.

If you have a current level above 7.5% it’s important to understand that any reduction in HbA1c level reduces your risk of long‑term complications. It can be done with a more regular blood glucose testing habit.

Take the quiz on blood glucose monitoring now!

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