The recalls of metformin, a drug used to treat type 2 diabetes, haven’t stopped. Since June through week at least nine companies have recalled the extended release version of this drug. These are all voluntary recalls. No adverse events were reported.
This week, Nostrum Laboratories, Inc. announced an immediate voluntary recall of four lots, two lots of 750 mg tablets and two lots of 500 mg tablets with extended release metformin HCl. Markans Pharma and Sun Pharmaceutical Industries also announced recalls this week. Markans now has 76 lots, 500 mg and 750 mg that it has remembered since the summer. The product is known as Time-Cap Labs. Sun announced in its recall a batch of Riomet ER, metformin hydrochloride, 500 mg per 5 ml. Inquiries to multiple companies for comment were not returned.
The culprit in all of these recalls is N-nitrosodimethylamine (NDMA), which is classified as a possible carcinogen. It’s found in water, meat, dairy products, and even vegetables. However, at high concentrations it can be dangerous. The FDA limit for NDMA is 0.096 nanograms per day. The FDA said in statements on its website that it began investigating NDMA levels in certain drugs in 2017 after learning that other countries are investigating the same problem on their drug distribution networks.
An FDA spokeswoman told Medical Daily that the agency has asked manufacturers and distributors of metformin to test all lots from overseas. If the lots are above the 0.096 nanograms, they’ll need to tell the agency, she said. One reason for the large number of recalls could be the agency’s use of new technology that can detect tiny amounts of drug contamination. Other sources of the contaminant could be due to the manufacturing process of the drug or chemical composition, according to the FDA.
Metformin treats type 2 diabetes by controlling blood sugar levels along with diet and exercise.
If you have received metformin from any of the recalled lots, it is important not to stop taking the medicine before talking to your doctor. Patients with type 2 diabetes can have dangerous side effects if they stop taking metformin.
Consumers are advised to contact their doctor for alternative treatment and to let their doctor know if they have any problems with this drug.