FDA pushes metformin recalls for 5 drugmakers after carcinogen contamination

After the FDA identified a likely carcinogen in samples of the broadly used diabetes med metformin, recalls appeared likely. Now it's official.

The FDA said Thursday it had asked five metformin manufacturers to pull their extended-release metformin products, after pushing recalls of heartburn med Zantac and "sartan" blood pressure drugs for the same reason. A likely human carcinogen, N-Nitrosodimethylamine (NDMA), was discovered in samples of all three. 

The FDA said it was working with drugmakers to determine whether the recommended recalls would cause a shortage in the U.S. The move doesn't apply to metformin's immediate-release formulation, and the FDA specified that "there are additional manufacturers of the metformin ER formulation that supply a significant portion of the U.S. market, and their products are not being recalled."

The five firms that have been contacted are Apotex, Actavis, Amneal, Lupin and Marksans. Both Amneal and Apotex have announced voluntarily recalls of their versions of extended-release metformin.

The recall announcement comes just hours after the FDA declined to say whether it would pursue voluntary recalls after discovering NDMA contamination in tests metformin samples. 

RELATED: FDA finds likely carcinogen in common diabetes drug metformin. Will recalls follow?