The Food and Drug Administration said late Thursday that several batches of the drug metformin tested positive for unsafe levels of N-Nitrosodimethylamine, a possible cancer-causing chemical that can form as a manufacturing byproduct.
People with Type 2 diabetes use metformin alone or with other drugs to help control their blood sugar levels.
Patients should continue taking metformin drugs until their doctor can prescribe a replacement, the FDA said in a statement, noting the risks of discontinuing.
Regulators are still assessing whether the recalls will lead to shortages of metformin, but noted that a number of other companies make generic versions of the drugs that don’t appear to be affected by the issue.
Drugmaker Apotex Corp. recalled its extended-release metformin distributed in the U.S. earlier this week after the FDA found contamination in one lot.
