According to the U.S. Food and Drug Administration, a certain brand of diabetes blood sugar testing strips has been recalled by its creator Nova Diabetes Care. These diabetes testing strips may be giving users false, abnormally high readings.

Twenty-one lots of the Nova Max Glucose Test Strips and the Nova Max Plus glucose meter kits that contain the testing strips are part of the voluntary recall.

One expert calls the recall “concerning.”According to Dr. Alyson Myers, an endocrinologist at North Shore University Hospital in Manhasset, N.Y. “This is especially worrisome for patients who use insulin, as they depend on their fasting blood sugars to determine the amount of insulin they require.  “As a result, patients may over-correct their blood sugars, causing hypoglycemia [low blood sugar], which in severe cases can lead to loss of consciousness or permanent neurological damage.”

“The symptoms of low blood glucose include shaking, sweating and confusion.” “People can pass out or have seizures if low blood glucose is not treated with glucose or sweet drinks right away,” says another expert,Virginia Peragallo-Dittko, director of the Diabetes and Obesity Institute at Winthrop-University Hospital in Mineola, NY.

Nova Diabetes Care states it has notified all registered users about the recall, as well as health care providers who recommend the product. Pharmacies and other companies that distribute them have also been notified.

Patients should immediately stop using the test strips from the recalled lots, the FDA said. To check and confirm if you have the affected test strips from the recalled visit the  Nova Diabetes Care’s website or by call the company at 1-800-681-7390.

Diabetic patients should be aware of both high blood sugar (hyperglycemia) and low blood sugar symptoms and should contact their health care provider for additional advice on how to treat the symptoms, states the  FDA.