Abbott began a medical device correction for certain FreeStyle Libre 3 and FreeStyle Libre 3 Plus continuous glucose monitoring (CGM) sensors in the U.S. after internal testing discovered some sensors may provide incorrect low glucose readings.

Incorrect glucose readings over an extended time period, if not detected, can lead to incorrect treatment decisions for people living with diabetes. These include excessive carbohydrate intake or delaying doses of insulin—these decisions can cause health risks like potential injury or death, as well as other less serious complications.

Abbott identified and resolved the issue’s cause, which was related to one production line that makes Libre 3 and Libre 3 Plus sensors. The company said it is producing sensors to fulfill replacement and new orders and doesn’t anticipate significant supply disruptions.

The corrective action impacts about three million Libre 3 and Libre 3 Plus sensors in the U.S. from that production line, about half of which are estimated to have expired or been used. Abbott received reports of 736 adverse events (57 in the U.S.) and seven deaths (none in the U.S.) possibly related to this issue.

Abbott said consumers should visit www.FreeStyleCheck.com to confirm if their sensor is potentially impacted by the device correction and that it will replace potentially affected sensors at no charge.

If consumers are wearing or have a sensor that was confirmed as possible impacted, the company advised to immediately continue or remove it. Abbott also said that “Consumers should use a blood glucose meter or the built-in meter in the FreeStyle Libre 3 reader to make treatment decisions when sensor readings don’t match symptoms or expectations.”