Viona Pharmaceuticals Recalls Metformin Extended-Release Tablets

The U.S. Food and Drug Administration (FDA) is notifying doctors and people who take metformin that Viona Pharmaceuticals has voluntarily recalled 33 lots of metformin hydrochloride extended-release (ER) tablets, USP 750 mg to the retail level. The drug has been recalled because of an N-nitrosodimethylamine (NDMA) impurity.¹

Metformin is a medicine that is used to treat type 2 diabetes. Used along with a healthy diet and exercise plan, metformin increases the body's sensitivity to insulin and decreases sugar absorption through the intestines. This leads to reduced glucose (sugar) in the blood.²

There have been several recalls of ER metformin from various makers in the last year due to NDMA impurities and high levels of NDMA. More information about recalls is available on the FDA’s drug recall page.³

This recall does not include immediate-release (IR) metformin. There has been no evidence of high levels of NDMA or NDMA impurities in IR metformin.

What is NDMA?

NDMA is a substance found naturally in the environment. It is found in water and foods including meat, dairy products, and vegetables. According to lab tests, NDMA is a carcinogen, which means it could cause cancer when high levels are taken over a long period of time.¹

The acceptable intake of NDMA is 96 nanograms per day. Because NDMA has been found in some ER metformin batches, the FDA is looking into why it is there. While low levels of NDMA do not cause harm, high levels of NDMA, when taken over a long period of time, have cause for concern.⁴

What does this mean for those taking metformin?

Your metformin may be part of the lots that are being recalled. Call your pharmacy to find out whether you are taking the Viona metformin that has been taken off the market. If it is, they may be able to give you metformin from another, unaffected batch.

However, this does not mean you should stop taking your metformin. The FDA recommends that you continue taking metformin as prescribed and to contact your doctor. It is dangerous to suddenly stop taking metformin without first checking with your doctor.¹

If your pharmacist can provide you with metformin made by a different company or from a batch that has not been recalled, be sure to bring in your current medicine. They can dispose of it safely.

However, if you cannot get a refill of unaffected metformin, talk with your doctor about next steps and what they advise. They may be able to prescribe you a different medicine or a different brand of metformin.