Glucose control solution is a liquid containing a known glucose concentration. This solution serves as a quality check for blood glucose monitoring systems. Its purpose is to verify that a glucose meter and its test strips are functioning accurately. Using this solution helps ensure that the numerical values displayed by the meter are reliable, which is important for effective diabetes management.
Understanding Unopened Expiration
Every bottle of glucose control solution comes with an expiration date printed on its label or packaging. This date indicates the period during which the solution remains stable and accurate when the bottle remains sealed in its original, unopened state. It signifies the manufacturer’s assurance of the product’s chemical integrity and performance under specified storage conditions before it is first exposed to air. Any solution that has passed this date should be discarded, as its composition may have degraded, leading to unreliable test results.
Shelf Life After Opening
Once a bottle of glucose control solution is opened, its usable lifespan shortens. Most manufacturers recommend discarding the solution 90 days (three months) after it has been opened for the first time. However, some brands may specify a longer period, such as six months, so it is important to consult the specific product instructions. To track this timeline, writing the date of opening directly on the bottle label is a recommended practice. The solution should always be discarded after this specified “opened” period, or by the printed expiration date, whichever comes first.
The reason for this reduced shelf life after opening is due to environmental exposure. Control solutions are typically composed of sugar, water, and various stabilizers. Once the seal is broken, the solution becomes susceptible to degradation from atmospheric oxygen, changes in temperature, and humidity. Unlike blood, control solutions do not contain blood cells and are less viscous, which can make them more sensitive to these external factors once exposed to the environment.
Optimizing Solution Longevity Through Storage
Proper storage conditions are required to maintain the stability and accuracy of glucose control solution. The solution should be stored at room temperature, generally within a range of 15-30°C (59-86°F). Avoid exposing the solution to extreme temperatures (very hot or very cold), as these can accelerate its degradation. Specifically, refrigeration or freezing is not recommended for most control solutions. If the solution becomes cold, it should be allowed to warm to room temperature for at least 30 minutes before use to ensure accurate results.
Protection from light is also important; store the bottle away from direct sunlight. After each use, the cap must be securely tightened. This prevents air from entering the bottle, which can introduce contaminants and promote chemical breakdown. Failure to follow these storage guidelines can lead to premature degradation, rendering it unreliable even within its stated shelf life.
Signs a Solution is No Longer Usable
Even when stored correctly and within its specified lifespan, a glucose control solution can become compromised. One indicator of potential degradation is a change in its physical appearance. While specific visual cues are not always detailed, discoloration, cloudiness, or the presence of particulate matter could signal that the solution is no longer suitable for use.
The most definitive sign that a solution may be compromised is when control tests yield results that fall outside the expected range printed on the test strip vial. This discrepancy indicates that the meter, the test strips, or the control solution is not functioning as intended. Other situations that might prompt suspicion include accidentally leaving the bottle uncapped, dropping the bottle, or exposing it to conditions beyond the recommended storage parameters. In such instances, replace the solution to ensure accurate testing.
Risks of Inaccurate Control Solution Readings
Using an expired or degraded glucose control solution can lead to inaccurate test results, with significant implications for diabetes management. When control readings are unreliable, they fail to indicate if the blood glucose meter and test strips are performing as expected. This can result in misinterpretations of blood glucose levels.
Such misinterpretations can lead to incorrect treatment decisions, such as inappropriate insulin administration or poor dietary choices. These errors can contribute to serious health complications, including hypoglycemia (dangerously low blood sugar) or hyperglycemia (elevated blood sugar). In severe cases, prolonged hyperglycemia can lead to diabetic ketoacidosis. Adhering to proper usage and storage guidelines for control solution is important for reliable results and effective diabetes care.