Users don't have to get rid of their FreeStyle Libre products, the FDA says, but should charge them only with the provided equipment.
CNN  — 

At least seven fires and one injury that were related to some FreeStyle Libre glucose monitor products have led the US Food and Drug Administration to issue a Class I recall, the agency’s strongest, which suggests that use of a device could cause “serious injuries or death.”

The manufacturer, Abbott, says there have been 206 incidents related to these monitors since 2014. But no users have died due to the problem, nor have there been any serious adverse health consequences.

The issue affects more than 4.2 million devices across the US, the FDA says.

Abbott initiated a voluntary medical device correction in February on its FreeStyle Libre, FreeStyle Libre 14 day and FreeStyle Libre 2 Readers in the US because of reports from some users that the readers’ lithium-ion batteries swelled, overheated and, in some cases, generated sparks or even caused a fire.

“No FreeStyle Libre readers are being physically recalled and customers can continue to safely use their readers with the Abbott-provided USB cable and power adapter. Customers do not need to return their readers. The steps outlined at www.FreeStyleBattery.com provide guidance on how to properly store, charge and use a reader and its accompanying USB cable and power adapter,” Abbott told CNN in an email Friday.

The company sent letters to some users of the FreeStyle Libre readers on February 13.

People with diabetes use glucose monitors to check their blood sugar levels because of problems with how their body makes or uses insulin, a hormone that helps blood sugar enter cells, where it is used for energy. Without insulin, sugar can build up in the bloodstream and break down the body’s own fat and muscle.

A continuous glucose monitor uses a handheld device that reads a sensor placed on the back of the person’s upper arm to capture real-time glucose levels.

The monitor used with the FreeStyle Libre line uses lithium-ion batteries similar to those in a mobile phone. The battery is recharged with a yellow USB cable that Abbott provides with the equipment and which limits electric current to safely charge the battery. Use of other USB cables or power adapters, along with misuse of the equipment such as damage or exposure to liquids, may increase the risk of fire, the FDA’s recall says.

The problem involves only the reader, not the sensor that the person wears on their arm.

Unlike more common recalls in which customers are told to dispose of or return their items, this type of correction instructs users to continue using their devices but only with the equipment provided to recharge the device. The equipment should also be properly stored between temperatures of -4 and 140 degrees Fahrenheit. The reader should never be put in water, and the USB port should be kept clean. More information is available in the device’s user guide.

Users of these glucose monitoring devices also have the option to use an app on their phone to receive the glucose data, but this requires a new sensor, the FDA said.

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Customers who have questions or who want to learn about testing, storing charging or using their reader can visit www.FreeStyleBattery.com or contact Abbott customer service at 1-855-632-8658. Customers may also contact Abbott if they need a replacement power adapter or yellow USB cable.

Correction: This story has been updated to reflect the years of the incidents related to these monitors.