The Food and Drug Administration announced it is recalling implantable infusion pumps manufactured by the medical technology company Medtronic after discovering the devices may malfunction due to a film that forms on its battery.

Federal health officials are warning patients that the recalled drug pumps, called the SynchroMed II, may fail to deliver drugs used to treat chronic pain, spasms and certain cancers. When the pumps stop working, the FDA said patients may be at risk for either recurrent or withdrawal symptoms that could be life-threatening.

The company has determined that the batteries in models 8637-20 and 8637-40 of the device may be defective.

Medtronic, based in Minneapolis, Minn., first notified physicians of the issue in July and has since updated the pump's design.  At the time, the company said it has received 55 adverse event reports related to the battery problem out of the nearly 140,000 pumps implanted worldwide, as of May 31, 2011.

Although the SynchroMed II pump is designed to last for up to 84 months, the batter-related malfunctions occurred between 45 and 78 months after the implant, according to Medtronic.

Another model of the pump was recalled in February due to a problem with its refill kits, which could potentially result in both a drug overdose and underdose.

Medtronic does not recommend removing the devices from patients who are already implanted with them if they have been functioning properly. However, it said patients should contact their doctors immediately if they hear a device alarm go off or if they're symptoms return, the FDA reports.

Medtronic's Web site includes a page where customers can enter serial numbers to determine whether their pump should be returned, accessible here.