The U.S. Food and Drug Administration authorized the Libre Duo 10 Day Continuous Dual Glucose Ketone Monitoring System for people aged 2 years and older living with diabetes, according to an FDA press announcement provided in the cluster. The agency described the device as the first wearable in the United States that continuously monitors ketone levels. The FDA also said it is the first device globally to continuously monitor both ketones and blood sugar, or glucose, together in a single wearable. The clinical use case is early visibility into diabetic ketoacidosis risk. The FDA cited Centers for Disease Control and Prevention estimates that 40.1 million Americans are living with diabetes, including an estimated 2.1 million Americans with type 1 diabetes. For people at risk, glucose alone may not show the full picture: ketones can rise when the body is using fat instead of glucose for energy, and excessive ketone production can lead to diabetic ketoacidosis, a serious complication that can develop quickly and become life-threatening if untreated. Until this authorization, the FDA said people who needed to monitor ketones had to use separate tests that provided a single point-in-time measurement. That approach could show a ketone level at the moment of testing, but not whether the level was rising or falling. Libre Duo 10 Day is designed to measure both ketone and glucose levels in fluid just beneath the skin every minute, day and night, according to the FDA. Readings are sent wirelessly to a compatible smartphone, where users can view current ketone and glucose levels and see whether those readings are trending up or down. The device can also send automatic alerts if ketone levels reach a concerning threshold. The FDA said that may help patients and caregivers recognize rising ketones before diabetic ketoacidosis becomes a medical emergency, while noting that ketone information should be interpreted alongside glucose readings and symptoms. The authorization was based on the FDA’s review of clinical and performance data submitted by the device sponsor. The clinical program included six clinical studies with more than 600 participants aged 2 years and older, evaluating the device’s ketone and glucose monitoring accuracy across a range of ketone and glucose levels. According to the FDA, the results showed the device accurately tracked clinically meaningful differences in ketone levels across its 10-day wear period, including identifying elevated ketone levels before the onset of diabetic ketoacidosis. The agency also said the authorization aligns with its Home as a Health Care Hub Initiative, which focuses on patient-centered devices that fit into care at home. Who benefits: People aged 2 and older living with diabetes who need ketone and glucose monitoring are the stated user group. Caregivers may also benefit from trend data and automatic alerts described by the FDA. Who's exposed: The provided material does not name competitors or quantify commercial exposure. Existing ketone testing approaches are indirectly exposed because the FDA describes them as separate, point-in-time tests rather than continuous monitoring.