A Johnson & Johnson company is recalling an advanced pain patch system for post-surgery hospital patients after some units of the needleless system were found to possibly be able to activate themselves, posing a potential risk of narcotic overdose.

The Ionsys transdermal system has been recalled from the 11 countries in Europe where it has been on the market since being launched in January, Greg Panico, a spokesman for J&J's Ortho McNeil unit, said Thursday. The defect was found among products being prepared for shipment at a distribution center, he said, and there have been no reports of patients being harmed.

The product has never been on the market in the U.S., although it was approved at one point.

Ionsys was designed as an advance over current systems that let hospitalized patients with significant pain press a button to get an intravenous dose of a powerful painkiller. Instead, it uses a low-intensity electrical field, barely noticeable to the patient, that rapidly moves the drug inside into the patient's skin and then bloodstream, according to Panico.