Feb. 6, 2020 -- The FDA says it has no plans to recall any metformin products, used to treat type 2 diabetes, after tests did not show any evidence of contamination with N-nitrosodimethylamine (NDMA) at levels that would cause concern.
The FDA began testing samples of metformin for the carcinogen NDMA at the end of last year. Contamination with this substance has led to recalls of blood pressure and heartburn medications within the past 2 years.
That announcement came on the heels of a recall of three versions of metformin in Singapore and the European Medicines Agency's request that drugmakers test for NDMA.
This week, the FDA posted laboratory results in which NDMA levels in some metformin products ranged from "not detectable to low."
"To date, no sample of metformin that FDA has tested exceeds the acceptable daily intake for NDMA. FDA has not recommended metformin recalls in the US," the agency says.
More than 30 million people in the United States have diabetes; 90% to 95% of cases are of type 2. Metformin is the fourth most-prescribed drug in the United States.
"Patients should continue taking metformin to keep their diabetes under control," the FDA says. "It could be dangerous for patients with this serious condition to stop taking their metformin without first talking to their health care professionals."
The agency plans to post the methods used in laboratory testing of metformin soon. It’s working with international regulators to share testing results for metformin, along with testing results for other drugs.
The FDA says it will continue to monitor NDMA in metformin, along with other drug products, and will provide timely updates of developments, including product recalls.