A drug often prescribed to diabetes patients is being investigated for traces of a probable carcinogen after it was recalled abroad, the U.S. Food and Drug Administration said.
Health officials are investigating whether Metformin sold in the U.S. contains NDMA, a contaminant that has been linked to cancer, the FDA said in a news release.
Testing will also look into whether the amount of NDMA in the drug is above the acceptable daily intake limit of 96 nanograms.
The drug is used to control high blood sugar in patients with type 2 diabetes.
The FDA told patients to continue to use Metformin while the investigation continues because there are no alternative medications that treat type 2 diabetes the same way.
Everyone is exposed to some level of NDMA, which is a common contaminant found in water and foods including cured and grilled meats, dairy products and vegetables, health officials said.
The substance may increase the risk of cancer in people who are exposed to high levels over long periods of time.
"A person taking a drug that contains NDMA at-or-below the acceptable daily intake limit every day for 70 years is not expected to have an increased risk of cancer," the FDA said.
Metformin drugs have been recalled in Singapore, and other regulatory agencies in Europe are also investigating the presence of the contaminant.
"Based on the information we have available, the levels of NDMA seen outside the U.S. are within the range that is naturally occurring in some foods and in water," the FDA said.
There have been no recalls of Metformin in the U.S.
"The agency will also work with companies to test samples of metformin sold in the U.S. and will recommend recalls as appropriate if high levels of NDMA are found," the FDA said. "If as part of our investigation, metformin drugs are recalled, the FDA will provide timely updates to patients and health care professionals."
Earlier this year, CVS announced it will be taking Zantac and other ranitidine heartburn drugs off its shelves after health officials said that the drug contains low levels of NDMA.