Most people with diabetes need to have their blood glucose levels measured regularly. The results of the measurements can help manage blood glucose so that diabetes complications can be avoided.
There are several ways to measure blood glucose.
- Measure from the fingertip: Prick your finger with a thin, sharp needle (called a prick) and put a drop of blood on the test strip. Then, place this test strip into a blood glucose meter that displays blood glucose levels. The results are available in less than 15 seconds and this information can be stored for future use. Some meters can display the average blood glucose level over time and show tables and graphs of past measurements. Blood glucose meters and test strips can be purchased at your local pharmacy.
- Glucose meters that measure other areas: Newer blood glucose meters can take blood from areas other than the fingertip to measure blood glucose, such as the upper arm, forearm, base of the thumb, and thigh. It may be possible to get different results than with fingertip blood. Fingertip blood can show faster changes in blood glucose levels than other measurement sites. This is especially true when blood glucose changes rapidly, such as after a meal or after exercise. If blood glucose is measured when symptoms of hypoglycemia are present, it should be measured using fingertip blood whenever possible, as these readings will be more accurate.
- An ambulatory glucose monitoring system: Also known as an interstitial glucose measurement device, it can be used in combination with an insulin pump. Its measurements are similar to glucose results measured by fingertip-test paper and can show patterns and trends in results over time.
When should I measure blood glucose?
Glucose may need to be measured several times a day, such as before meals or exercise, at bedtime, before driving, and when blood glucose levels are thought to be low.
Everyone is different, so consult your doctor about when you should measure your blood glucose and how often you should measure it. If you are sick, you may need to measure your blood glucose more often.
What factors can affect the results?
If there are certain medical conditions, such as anemia or gout, or if it is hot or humid, or if you are at a high altitude, these factors may affect blood glucose levels.
If you continue to see abnormal results, recalibrate your glucose meter and check the test strips.
The table below gives an idea of what blood glucose levels should be during the day. Each person’s ideal blood glucose range may be different from others and will change throughout the day.
| Ideal range | |
| Before Meal | 70~130mg/dl |
| Less than 180mg/dl |
Home blood glucose monitoring and glycated hemoglobin (HbA1c)
Monitoring HbA1c levels is also important for diabetes control. Many home glucose monitors can display average blood glucose readings that correspond somewhat to HbA1c.
| HbA1c(%) | |
| 126 | 6 |
| 154 | 7 |
| 183 | 8 |
| 212 | 9 |
| 240 | 10 |
| 269 | 11 |
| 298 | 12 |
When should I seek medical attention?
Consult your doctor about target blood glucose ranges, making a plan for how to handle high or low blood glucose readings, and when to seek medical attention. Know the symptoms of high or low blood glucose and what you can do when symptoms start.
How do I record my blood glucose measurements?
Make a record of any blood, urine, or ketone body tests. Most blood glucose monitors also have a memory function. Recording can alert you to any problems or trends. These measurement records can help your doctor make any necessary changes in your meal plan, medications, or exercise program. Bring these records with you to every doctor’s appointment.