Lifestyle

Your Metformin May Have Contained a Cancer-Causing Chemical. Here’s How to File a Claim.

By Mike Harper · May 29, 2026

Metformin is one of the most commonly prescribed drugs in America — a frontline treatment for Type 2 diabetes taken by approximately 37 million Americans. Between 2019 and 2020, the FDA found that certain formulations of metformin contained NDMA — N-Nitrosodimethylamine — a probable human carcinogen that the WHO has classified as a Group 2A cancer risk. Multiple manufacturers recalled their products. Three of them have now settled a class action lawsuit over the contamination.

Teva Pharmaceuticals, Granules USA, and Heritage Pharmaceuticals agreed to a combined $5.55 million settlement to resolve claims that their extended-release metformin products contained NDMA at levels exceeding FDA safety thresholds. The settlement received preliminary court approval in May 2026. The claim filing deadline is July 10, 2026.

Who qualifies:

US residents who purchased extended-release metformin manufactured by Teva, Granules USA, or Heritage Pharmaceuticals between January 2012 and October 2020. The contamination issue was primarily identified in extended-release formulations — the tablets designed to release the drug slowly over several hours — rather than immediate-release versions. If you filled a prescription for metformin ER or metformin XR during that period, you may be eligible regardless of whether you experienced any health effects.

You do not need to have been diagnosed with cancer to file a claim. The settlement compensates patients who purchased the contaminated product, not only those who suffered documented health consequences.

How much will you receive:

Individual payments will be modest given the $5.55 million total fund. The final per-claimant amount depends on the total number of valid claims filed and the court’s approval of attorneys’ fees. Claimants who can document multiple purchases over a longer period may receive higher payments. Submit your claim with whatever pharmacy records, prescription receipts, or insurance EOB statements you have available.

How to file:

Visit the settlement website and complete the claim form before July 10, 2026. Keep copies of any pharmacy records you submit. Claims filed after the July 10 deadline will not be accepted.

One important note:

If you currently take metformin extended-release, talk to your doctor before making any changes to your medication. The FDA’s 2020 recalls covered specific lots and manufacturers — not all metformin ER products. Your current prescription may be from a different manufacturer or formulation that was not affected by the contamination. Do not stop taking a prescribed medication without medical guidance.