Freestyle Libre 2 Lawsuit Alleges Faulty Blood Sugar Readings Resulted in Near-Fatal DKA Event

Lawsuit claims the CGM sensor displayed normal readings despite woman having dangerously elevated glucose levels.

A Louisiana woman has filed a product liability lawsuit alleging a Freestyle Libre 2 continuous glucose monitor (CGM) malfunctioned, causing her to delay treatment and suffer a diabetic ketoacidosis (DKA) event.

The complaint (PDF) was brought by Sheila Connoly in the U.S. District Court for the Eastern District of Louisiana on April 21. It names Abbott Diabetes Care Inc. and Abbott Laboratories, the device manufacturers, as defendants.

Connoly claims she relied on a Freestyle Libre 2 device to manage her Type 1 diabetes, yet in December 2025 it failed to reflect her actual condition, which hospital testing later revealed involved blood sugar levels near 700 mg/dL. 

Freestyle Libre CGM Risks

Freestyle Libre CGMs are small medical devices that track a person’s blood sugar levels in real time throughout the day and night. Like most CGMs, Freestyle Libre systems use a tiny sensor inserted just under the skin, usually on the upper arm or abdomen, to measure glucose levels in the fluid between cells. The sensor sends readings wirelessly to a receiver, smartphone app or insulin pump, typically updating every few minutes.

Despite these and similar devices being used by millions of people, a number of recent Freestyle Libre lawsuits claim that malfunctions in these systems have led individuals to suffer a range of diabetic side effects, including hypoglycemia, hyperglycemia and DKA.

Diabetic ketoacidosis is a serious, potentially life-threatening complication of diabetes that occurs when the body does not have enough insulin to use glucose for energy. Without insulin, the body begins breaking down fat for fuel, which produces acids called ketones. When ketones build up in the bloodstream, they make the blood too acidic, disrupting normal organ function, which can lead to severe dehydration, loss of consciousness and even death.

Freestyle Libre 2 DKA Allegations

According to the lawsuit, Connoly began using a Freestyle Libre 2 system in 2022. She says that she routinely depended on the device to monitor her blood sugar levels and guide insulin use throughout the day.

However, on December 15, 2025, the lawsuit states she received what appeared to be a moderately elevated reading of about 190 mg/dL, prompting her to administer insulin, after which her glucose levels appeared to return to normal.

The following day, Connoly began feeling ill and again relied on the CGM, which reported a normal reading of about 167 mg/dL. Despite those readings, her condition rapidly deteriorated, and she was taken to a hospital, where medical testing revealed her actual blood glucose level was approximately 700 mg/dL and she was suffering from DKA.

The complaint alleges the device provided falsely low or normal readings during a critical period when her blood sugar was dangerously elevated, delaying appropriate treatment and nearly resulting in her death.

Following the incident, Connoly says she was hospitalized in an intensive care unit for several days and experienced ongoing symptoms including weakness, disorientation and illness, as well as missed time from work.

The lawsuit claims the Freestyle Libre 2 and related CGM systems are defectively designed or manufactured, causing them to report inaccurate glucose readings that can mislead users making real-time treatment decisions.

According to the allegations, these inaccuracies pose significant safety risks because patients rely on the devices to determine insulin dosing and other critical interventions, meaning false readings can result in delayed care or inappropriate treatment decisions.

Connoly maintains she did not contribute to the incident and that the device malfunction was the direct cause of her injuries, including the development of DKA and associated complications.

“Upon information and belief, Plaintiff’s Freestyle Libre 2 and/or Freestyle Libre 2 Plus CGM, which was manufactured, designed, constructed, and/or produced by Defendants, was defective due to a design and/or manufacturing flaw which caused the sensor to report falsely low glucose readings, even when users’ actual blood glucose levels are normal or elevated.”

— Sheila Connoly v. Abbott Diabetes Care Inc. et al

The complaint raises allegations under the Louisiana Products Liability Act, claiming the manufacturers failed to design a safe product, breached warranties regarding accuracy, and failed to adequately warn users about the risk of inaccurate readings.

In addition to individual claims, the lawsuit seeks to represent a broader class of individuals who experienced similar issues with Freestyle Libre 2 devices. It is pursuing damages for medical expenses, lost wages, pain and suffering, and other losses.

Freestyle Libre CGM Lawsuits

As reports of adverse events tied to glucose monitors continue to increase, attorneys nationwide are reviewing potential FreeStyle Libre 2 and Libre 3 claims for individuals who allege they suffered serious injuries after relying on inaccurate sensor data.

Many individuals may qualify to pursue a claim if they or a loved one used a recalled FreeStyle Libre 3 or Libre 3 Plus device and experienced complications such as:

• Wrongful death
• Severe hypoglycemia
• Seizures
• Confusion or altered mental state
• Loss of consciousness
• Diabetic ketoacidosis
• Other acute metabolic emergencies
• Hospitalization

Attorneys are offering free case reviews to evaluate whether an Abbott FreeStyle Libre 3 lawsuit may be appropriate. They are also helping individuals understand their legal options and determine if they may be eligible to seek compensation.

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