Abbott and the U.S. Food and Drug Administration each announced the recall Wednesday. It affects six brands of testing strips distributed in the U.S. and Puerto Rico that Abbott will replace free of charge.

The drug and medical-device maker estimated the recalled products were worth less than $20 million in inventory, indicating a modest financial impact. Spokesman Scott Davies said the recall doesn't change Abbott's previously issued earnings guidance for this year.

Abbott's Diabetes Care business posted $938 million in sales through the first nine months of this year, representing 3.7% of the Abbott Park, Ill., company's total sales for that period.

Still, the recall adds to recent product setbacks for Abbott. Sales growth in the third quarter fell short of Wall Street's expectations, due partly to the September recall of about five million containers of Similac baby formula because of potential contamination by beetle parts or larvae. In October, the company withdrew the diet drug Meridia from the market at the FDA's request after the drug was linked to an increased risk for heart attacks and strokes.

The latest recall is related to certain test strips' inability to absorb enough blood. According to the FDA and the company, false results may lead patients to try to raise their blood glucose unnecessarily, or they may fail to treat elevated blood glucose because of a false, low reading. Both scenarios pose risks to a patient's health.

Strips exposed to warm weather or prolonged storage may be more likely to provide a false result.

The recall affects the Precision Xceed Pro, Precision Xtra, MediSense Optium, Optium, OptiumEZ and ReliOn Ultima brands. The test strips were manufactured between January and May of this year and are sold to customers through retail and online channels, the FDA said. They were also used in health-care facilities.

Abbott said blood glucose monitors aren't being recalled and said customers can continue to use those.

To determine if a product is being recalled, consumers can call 1-800-448-5234, or 1-800-709-7010 for Spanish-speaking consumers, or visit www.precisionoptiuminfo.com.