FDA authorizes wearable for continuous ketone tracking

A sensor worn on the skin will now track two signals through the night: ketones and glucose. The FDA has authorized Abbott’s Libre Duo 10 Day, which reads fluid just beneath the skin every minute, then sends the results wirelessly to a smartphone app that shows whether levels are rising or falling.

The device is aimed at an emergency that can build quietly. Ketones appear when the body burns fat instead of sugar, and excessive levels can lead to diabetic ketoacidosis, or DKA. The American Diabetes Association says DKA can worsen within hours and cause coma or death if untreated. Early symptoms are often mistaken for a stomach bug or infection, while most people do not keep a blood ketone meter at home.

Until now, blood or urine ketone tests captured a single moment. Libre Duo is designed to show the direction of travel and sound an alert when ketones reach a concerning level. Dr. Michelle Tarver, who directs the FDA’s Center for Devices and Radiological Health, said real-time information could create an opportunity for earlier intervention. Dr. Jennifer Sherr, a pediatric endocrinologist at Yale School of Medicine, described DKA as something that can develop quickly and whose early warning signs are often missed.

The authorization was supported by six studies involving more than 600 people. The FDA said the sensor accurately tracked meaningful changes in ketone levels across the full 10-day wear period and flagged elevated ketones before DKA took hold. Abbott says it is targeting people at higher risk of elevated ketones, including those taking insulin or glucose-lowering medicines.

In practical terms, the change is a warning system where many patients previously had only occasional tests—or no ketone measurement at home. Abbott plans to launch the sensor in the United States later this year and is working to connect it with automated insulin delivery systems. The FDA says the device’s readings should always be considered alongside glucose numbers and a person’s symptoms.