Accurate glucose monitoring is essential for people living with diabetes.
They claim to use non-invasive techniques, the FDA said in a statement.
These smartwatches and smart rings do not directly test blood glucose levels.
zamrznutitonovi / Getty Images
The devices are manufactured by dozens of companies and sold under multiple brand names.
The FDA did not call out any specific brands.
Using a machine that is not accurate can be life-threatening.
CGMs rely on a sensor that is inserted into an arm or stomach with a small needle.
Knowledge of glucose empowers patients to play a key role in their diabetes control.
The first continuous glucose monitor, made by Medtronic MiniMed, debuted in 1999.
It required calibration with a finger prick and was intended for use in a doctors office.
By 2006, DexCom introduced its first real-time continuous glucose monitor for individual use.
Many health insurers cover costs, supplies may require copays.
Some of theunapproved devicesare available online for as little as $40 for a one-time purchase.
But the ring itself cannot monitor your glucose levels.
Inaccurate measures for blood glucose can have a potentially devastating impact on people with diabetes.
Hirsch IB.Introduction: history of glucose monitoring.
In: Role of Continuous Glucose Monitoring in Diabetes Treatment.
Arlington (VA): American Diabetes Association; 2018 Aug. doi:10.2337/db20181-1
