Two pharmaceutical companies recently issued voluntary recalls for extended-release versions of the diabetes drug metformin, because it may contain high levels of a cancer-causing chemical, according to notices by the U.S. Food and Drug Administration.
Metformin tablets are a staple of diabetes care, reducing excess sugar in the blood. People with Type 2 diabetes use metformin alone or with other drugs to help control their blood sugar levels. More than 34 million people in the U.S. have this disease.
Back in May, the FDA told five drugmakers to recall their versions of metformin because several batches had tested positive for unsafe levels of the chemical N-Nitrosodimethylamine (NDMA). The agency had stepped up testing after the same chemical was found in dozens of shipments of heartburn drugs last year, triggering recalls of Zantac and other popular over-the-counter and prescription medications.
The latest recalled metformin tablets from Marksans Pharma and Sun Pharmaceutical Industries were sold under the brand names Time-Cap Labs and Riomet ER. The Marksans Pharma recall expands on an earlier recall of the same product from back in June. This week's recall added 76 more unexpired lots of its Metformin Hydrochloride Extended-Release Tablets, 500mg and 750mg.
Since the FDA's initial notice in May, 10 companies have recalled metformin extended-release tablets. The agency noted earlier this year that no contamination problems have been found in immediate-release metformin.
Patients should continue taking metformin drugs until their doctor can prescribe a replacement, the FDA said in a statement, noting the risks of discontinuing.
The Associated Press contributed to this report.