Blood glucose control solution is a simple but important part of home blood glucose testing. If you have ever wondered why your meter kit includes small bottles of liquid — or why your diabetes educator mentions checking accuracy — this guide explains what control solution is, when to use it, and why it does not recalibrate your meter.
The NHS recommends checking your meter when results seem inconsistent or after events that could affect accuracy. Control solution is the standard way to confirm your meter and test materials are working correctly before you rely on a reading for treatment decisions.
What is blood glucose control solution used for?
Control solution is used to check the accuracy of a blood glucose meter. If the accuracy of a blood glucose meter is not checked periodically, there is a risk that an inaccurate meter may go undetected. That could lead to incorrect treatment decisions and potentially harmful outcomes.
What is control solution?
Control solution is a liquid that contains a specific amount of glucose. Usually there are two solutions, with one having a low level of glucose and the second having a high level of glucose. Betachek supplies Control Solutions 1 and 2 for use with compatible meters and test cassettes.
How is control solution used?
To check a meter’s accuracy, a drop of control solution is used instead of a drop of blood when running a test. The test result is then compared to an acceptable range printed on the container label. If the result is within the acceptable range, then the meter is producing accurate results.
For step-by-step testing guidance — including when to run a control check — see our guide on how to use a blood glucose monitoring system.
When should control solution be used?
- After opening a new container of tests.
- After you have replaced the batteries.
- After you have cleaned your meter.
- If you obtain unexpected results.
- If you have left the cap off your container of test strips or test cassette.
- If the meter has been dropped or exposed to extreme heat (left in a hot car).
- Whenever you suspect the meter or test cassette may not be functioning properly.
Store unopened control solution according to the label, and discard once opened if the expiry date has passed or the liquid looks cloudy. Using fresh control solution helps ensure your accuracy check is meaningful.
Does control solution recalibrate a blood glucose meter?
No. Blood glucose meters are factory calibrated and cannot be recalibrated by the end user. If a control test falls outside the acceptable range on the label, contact the meter manufacturer or your diabetes care team — do not attempt to adjust the device yourself.
Related blood glucose guides
- How to use a blood glucose monitoring system
- What is a blood glucose monitoring system?
- mg/dL vs mmol/L: blood glucose units by country
