Watson Pharmaceuticals has recalled one lot of its 75-mcg/hour fentanyl transdermal system in the U.S. because a small number of patches were leaking a gel form of the pain medicine.

The recalled patches are from lot No. 92461850 with an Aug. 31, 2009, expiration date. They were shipped between Jan. 30 and March 19. No other strengths or lots were affected, and the company does not anticipate any product shortages as a result of the recall, according to its statement.

Accidental exposure to fentanyl gel may lead to serious adverse events, including respiratory depression and possibly fatal overdose. No injuries have been reported, Watson said.

The fentanyl system is the generic equivalent of Duragesic, which is indicated to manage moderate-to-severe chronic pain with continuous opioid administration for an extended period of time. Alza, a Johnson & Johnson subsidiary, manufactures the brand product.

Fentanyl patches have a history of recalls this year. PriCara in the U.S. and Janssen-Ortho in Canada voluntarily recalled all lots of their 25-mcg/hour Duragesic transdermal patches manufactured by Alza because of concerns that the patches might have a cut along one side of the drug reservoir, allowing the fentanyl gel to leak into the packaging. The recall involved patches with expiration dates on or before December 2009.