Metformin Class Action Lawsuit Filed Over Cancer-Causing NDMA Contamination

A number of generic drug manufacturers face a class action lawsuit over metformin, following the revelation that some versions of the widely used diabetes drug have been distributed with the cancer-causing chemical N-nitrosodimethylamine (NDMA).

Joseph Brzozowski filed the complaint (PDF) in the U.S. District Court for the District of New Jersey on March 3, seeking class action status to pursue damages for all generic metformin users who unknowingly took the pills, unaware that they were contaminated and may increase their risk of cancer.

Actavis, Teva Pharmaceuticals, CVS Health Corporation and up to 100 as-yet identified defendants are named in the lawsuit, which indicates that the manufacturers failed to warn users and the the medical community that contaminated metformin pills may contain the known carcinogen.

Did You Know?

Millions of Philips CPAP Machines Recalled

Philips DreamStation, CPAP and BiPAP machines sold in recent years may pose a risk of cancer, lung damage and other injuries.

Learn More

“At all times during the period alleged herein, Defendants represented and warranted to consumers that their generic metformin products were otherwise fit for their ordinary uses, and were otherwise manufactured and distributed in accordance with applicable laws and regulations,” the lawsuit states. “However, for years, Defendants willfully flouted federal current Good Manufacturing Practices and ignored other warning signs that Defendants’ Metformin products contained or likely contained NDMA and/or other impurities.”

NDMA is a chemical byproduct, which is considered a carcinogen. It used to result from making rocket fuel in the early 1900s, but today is only used in laboratory experiments to induce cancer in animal test subjects.

In recent months, detection of the chemical in other drugs has resulted in wide scale Zantac recalls and valsartan recalls, after it was confirmed that dangerously high levels of NDMA were present in the popular heartburn and blood pressure medications.

Late last year, reports first warned about the potential risk that problems may also be impacting metformin, after some versions of the drug sold outside the United States tested positive for NDMA, raising concerns that metformin recalls may be necessary. However, the FDA indicated that testing of products distributed in the U.S. found that the metformin NDMA contamination levels were undetectable or below federal limits for exposure to the chemical.

Earlier this month, the independent online pharmacy Valisure filed a citizen’s petition urging the FDA to issue metformin recalls, after independent testing found levels of NDMA in certain pills that was higher than the agency’s recommended daily exposure threshold of 96 nanograms.

Metformin is sold under several brand names, including Glucophage, Carbophage, Fortamet, Diabex and Riomet. It is also often used in combination with other diabetes drugs, and is widely used worldwide.

According to the metformin class action lawsuit filed days after the recall petition, Brzozowski took metformin from April 2009 through September 2017, during which time he received a number of the products that were found to contain high levels of NDMA. The lawsuit indicates those drugs should be considered adulterated and illegally sold due to their NDMA content, which made them unfit for ordinary use.

NDMA In Zantac and Valsartan

Valisure is the same pharmacy which first raised alarms about the link between Zantac and cancer in September 2019, after finding that some pills contained 3,000,000 ng of NDMA. This led to further FDA testing, which confirmed the high levels were present in virtually all Zantac products and their generic equivalents, resulting in a widespread, and still ongoing, Zantac recall.

Concerns over NDMA drug contamination in pharmaceutical drugs began to emerge in 2018, with an investigation into a number of generic blood pressure drugs that were found to contain high levels of the chemical. This led to several rounds of recalls for valsartan, losartan and irbesartan, and investigations suggested that NDMC may have contaminated the drugs as a by-product of changes in the generic drug manufacturing process.

In response to concerns about the cancer risk with valsartan and other similar drugs, and the possibility of shortages for the hypertension drugs, the FDA established a permissible daily limit for NDMA at 96 nanograms, requiring pills that may expose users to more of the carcinogen to be recalled.

While drug makers and federal regulators indicate they are continuing to investigate the underlying cause of both the NDMA contamination, many consumers diagnosed with cancer in recent years are now pursuing valsartan lawsuits and Zantac lawsuits, alleging they may have avoided a cancer diagnosis if other treatments had been used.

Image Credit: |test caption

42 Comments

  • ChristinaSeptember 5, 2023 at 5:25 am

    I took metformin for 2 years and this past January I was diagnosed with HER II breast cancer.

  • TonyAugust 21, 2023 at 3:04 pm

    My husband was diagnosed with pancreatic cancer in 2020. He had surgery in November of 2021. Thanksgiving day after coming home from hospital he almost died. He has Type II Diabetes and has taken Metformin for years.

  • mikeJuly 24, 2023 at 5:51 pm

    MY WIFE OFELIA MORELL AGE 61, CAME DOWN WITH BREAST CANCER SOME WEEKS AGO. AFTER SURGERY SHE IS UNDERGOING PAINFUL RADIO AND CHEMOTHERAPY. SHE HAS NO SIGNPOSTS FOR CANCER: NO RELATIVES EVER AFFECTED BY IT; HER WEIGHT IS NORMAL, SHE’S NEVER TAKEN ILLEGAL DRUGS, SMOKED, OR DRANK ALCOHOL; SHE DRINKS PURIFIED, RATHER THAN TAP WATER--A VERY CLEAN PERSON. FOR AT LEAST 30 YEARS SHE'S BEEN PRESCRIBED AND [Show More]MY WIFE OFELIA MORELL AGE 61, CAME DOWN WITH BREAST CANCER SOME WEEKS AGO. AFTER SURGERY SHE IS UNDERGOING PAINFUL RADIO AND CHEMOTHERAPY. SHE HAS NO SIGNPOSTS FOR CANCER: NO RELATIVES EVER AFFECTED BY IT; HER WEIGHT IS NORMAL, SHE’S NEVER TAKEN ILLEGAL DRUGS, SMOKED, OR DRANK ALCOHOL; SHE DRINKS PURIFIED, RATHER THAN TAP WATER--A VERY CLEAN PERSON. FOR AT LEAST 30 YEARS SHE'S BEEN PRESCRIBED AND TAKEN METFORMIN FOR DIABETES AND LOSARTAN FOR BLOOD PRESSURE ONCE OR TWICE DAILY. BOTH MEDICAMENTS WERE FOUND TO CONTAIN NDMA, A CARCINOGEN. IF YOU'D LITIGATE THIS CASE VS. PHARMA, ET. AL, FOR MRS MORELL PLEASE LET ME KNOW.

  • JanettaJune 17, 2023 at 2:07 am

    Took it over 20years

  • LeannaMarch 26, 2023 at 11:16 pm

    I took Metformin for years and stopped because how badly they made me feel as far as I can remember. I have many health issues including pancreatic digestion issues, have had an abdominal aortic aneurysm rupture, neuropathy, growth on adrenal glad, sliding hernia and on and on. I'd be interested in hearing about any litigation on the drug and/or testing.

  • DeniseNovember 8, 2022 at 9:28 am

    I have took met Forman for over 10 years.on October 5th of this year I was diagnosed with kidney cancer.

  • JeanetteOctober 27, 2022 at 8:55 pm

    I need help with this.

  • JonathanAugust 28, 2022 at 4:18 pm

    I Hope everyone is successful in whatever they want to do

  • HaroldJuly 20, 2022 at 4:34 pm

    My wife has type 2 diabetes and was given metformin for several years.. She now has neuropathy, kidney, liver and intestine problems which are getting worse as time goes by…. I need to know where and who to contact so I can get help for my wife… and also file a complaint and class action suit…. PLEASE HELP !!!!!

  • ROBERTApril 17, 2021 at 9:11 am

    metforman producers have no clue what they have done they probibly dont even care. but ,My wife now has stage 4 colan cancer and it spred to her lungs . from taking there bad drug

  • AnnieApril 8, 2021 at 3:40 am

    My husband was treated for different conditions DM with Glucophage for 6 years , HBP on Valsartan x 5 years. Until he was dropped in the hospital last August , he complained of hip pain .within 2 months he was diagnosed with Liver ( Hepatobilliary Ca to be exact ) cancer radiating to the Bone in January The oncologist said that this is extremely rare form of Cancer ,like less then 1% ,they [Show More]My husband was treated for different conditions DM with Glucophage for 6 years , HBP on Valsartan x 5 years. Until he was dropped in the hospital last August , he complained of hip pain .within 2 months he was diagnosed with Liver ( Hepatobilliary Ca to be exact ) cancer radiating to the Bone in January The oncologist said that this is extremely rare form of Cancer ,like less then 1% ,they did the genetic studies ect ect,wanted to treat with Immunotherapy. He died 6 weeks later He was a strong,well built man ,never complained of any problems,no arthritis like many elderly people do . I swear that Glucophage & Valsartan caused that horrible Cancer ,the pain at the end was intractable ,so tragic .

  • MaggieMarch 31, 2021 at 3:53 pm

    I have just been diagnosed with metastatic lymphoma, I have been on Metformin for at least 12 years. I have smoked off and on over about 20 years, starting and quitting for year then seven years, and then started smoking again in March of 2020. Quit once again and so that could have played a factor and made this worse, but I have never had a blood test show the possiblity of cancer and my family [Show More]I have just been diagnosed with metastatic lymphoma, I have been on Metformin for at least 12 years. I have smoked off and on over about 20 years, starting and quitting for year then seven years, and then started smoking again in March of 2020. Quit once again and so that could have played a factor and made this worse, but I have never had a blood test show the possiblity of cancer and my family is not high risk. So I don't know what to think.

  • ConnieFebruary 20, 2021 at 6:16 pm

    I am doing lots of research now these past few months and learning more about the drug. Wondering if doctors new the terrible side effect and kept silent. As for Canadian drug companies like I hope they did not keep silent if they were aware of this problem. My sympathy to all those who have suffered from this drug.

  • DeniseDecember 4, 2020 at 8:06 pm

    My husband took metformin for years was diagnosed with stage 4 liver cancer in September of 2019. He passed away in January of 2020. He said it made him sick when he took metformin.

  • michelleDecember 3, 2020 at 12:03 pm

    I took metformin for years and ended up with breast cancer twice within less than five years .

  • PatriciaNovember 22, 2020 at 6:18 pm

    I have been on Metformin since 2004.I have upper respiratory infection keep one.I had to have open heart surgery back in 2018.I have to take stomach medicine every day.Now I’m on inhalers now.

  • MariaNovember 21, 2020 at 4:16 am

    I have been taking Metformin 1000 mg for years. On May 2020 I was diagnosed with kidney cancer my kidney was removed on June 2020.

  • CarolNovember 9, 2020 at 5:26 pm

    my husband took metformin for years, he was diagnosed with liver and lung cancer in May of 2019 and passed away in September of 2019. What course of action should I take?

  • CherylOctober 21, 2020 at 1:29 am

    My father was on Metformin for many years and passed away last month from stomach cancer. I would like an attorney to contact my family as we believe the Metformin could have played a major part in his gastric cancer.

  • JohnOctober 12, 2020 at 8:48 pm

    I was on Metformin for quite a few years when I suddenly developed kidney cancer. The doctors immediately took me of this drug. Did they know something that I did not know? I had one kidney removed and the other stopped functioning properly within the following year. I have been on dialysis for the past six months.

  • CharlesOctober 11, 2020 at 1:53 pm

    I’ve been on metformin for several years. I had some sort of mass in my bladder removed a few years ago and had to have it removed surgically. I am under care of a new urologist that can handle the procedure in office if needed. I honestly think this medication is the cause of my issue. Never before in my life have I had a issue with that area. Seems odd that after taking this medication I have is[Show More]I’ve been on metformin for several years. I had some sort of mass in my bladder removed a few years ago and had to have it removed surgically. I am under care of a new urologist that can handle the procedure in office if needed. I honestly think this medication is the cause of my issue. Never before in my life have I had a issue with that area. Seems odd that after taking this medication I have issues.

  • RogerAugust 10, 2020 at 5:16 pm

    I was on metformin for about 8 years. It has ruined my kidneys. I am now stage 4 renal.

  • natJuly 26, 2020 at 7:38 pm

    my wife has breast cancer becauses of the metformin she takes that was recalled

  • earthJuly 14, 2020 at 2:50 pm

    nine years taking metformin, in recent five years had to apply for disability have chronic fatigue, metformin?

  • JuliaJuly 11, 2020 at 12:34 am

    My husband was taking metformin and he died of complications due to Myelodysplastia

  • ConnieJuly 10, 2020 at 8:19 pm

    Dear Greg, I am so sorry to hear you have pancreatic cancer. My husband Lui was a type 2 diabetic and was on Metformin for over 14 years . In March 2018 he was diagnosed with stage 4 pancreatic cancer and passed away 2 weeks later. .. I cannot say if it was caused by the Metformin but the side effects for him were terrible. Although we live in Canada I am not sure if the drug content is the sa[Show More]Dear Greg, I am so sorry to hear you have pancreatic cancer. My husband Lui was a type 2 diabetic and was on Metformin for over 14 years . In March 2018 he was diagnosed with stage 4 pancreatic cancer and passed away 2 weeks later. .. I cannot say if it was caused by the Metformin but the side effects for him were terrible. Although we live in Canada I am not sure if the drug content is the same as that of the USA I will keep you in my prayers and hope you can get proper medical help. God bless you. Connie

  • PANDAJuly 9, 2020 at 12:16 am

    The doctor described metformin for my PCOS about five years ago and I ended up at the hospital twice. I almost passed out while driving, my mouth would taste like metal, I constantly had and upset stomach, my blood pressure skyrocketed I had felt like I was poisoned. I went to my doctor and he said it wasn't the medication but when I got off of it I had bad withdrawals where I was vomiting and I h[Show More]The doctor described metformin for my PCOS about five years ago and I ended up at the hospital twice. I almost passed out while driving, my mouth would taste like metal, I constantly had and upset stomach, my blood pressure skyrocketed I had felt like I was poisoned. I went to my doctor and he said it wasn't the medication but when I got off of it I had bad withdrawals where I was vomiting and I had bad headaches where I couldn't sleep, my muscle turned soft and my stomach hasn't been the same since. In 2019 I went to a different doctor and she prescribed metformin for my PCOS I had told her about my previous experience and she said it couldn't have been metformin so I tried it again but this time I started with a fourth of a pill and I experienced the same side effects just not as severe as the first time. Never again and I always tell everyone not to take it.

  • A.S.June 26, 2020 at 10:53 am

    The FDA issued an alert in December of last year (2019) saying they were investigating whether Met sold in the US contained NDMA. In Feb of 2020, there were recalls in Canada. In March, an independent lab tested Met and found many lots from many manufacturers had high levels of NDMA and sent the FDA their findings, begging them to issue recalls. My metformin was not recalled until June 18th, 2020[Show More]The FDA issued an alert in December of last year (2019) saying they were investigating whether Met sold in the US contained NDMA. In Feb of 2020, there were recalls in Canada. In March, an independent lab tested Met and found many lots from many manufacturers had high levels of NDMA and sent the FDA their findings, begging them to issue recalls. My metformin was not recalled until June 18th, 2020, which was my first glimpse of this issue. The FDA knowingly let Americans ingest carcinogens for arguably 6 months, but certainly for the 3 months following receipt of the testing results from the independent lab. We need lawyers, we need cancer screenings on the dime of these companies, and we need it all to move more quickly than the FDA apparently can.

  • JoyceJune 22, 2020 at 1:30 pm

    I was diagnosed with breast cancer in February, no family history. I have been on metformin XR for 5 years

  • wilmaJune 22, 2020 at 10:35 am

    my husband pased may 20 he took metformin hcl1000 mg 2 times a day

  • MABELJune 17, 2020 at 7:41 pm

    I have taken Metformin 500 mg extended release since 2008.After 5 years I developed kidney cancer. I hope the discovery of the harmful chemical will help diabetic patients. Within my heart,I always felt that it was not diabetes, but metformin that was harmful to my body.I am thankful to know about it now. i will not take it again. and I will never take it again

  • AngelaJune 15, 2020 at 6:29 pm

    I had surgery on both of my breasts my kidney function drop low 2 months ago and now they want me to have a test on my thyroid due to cancer

  • LindaJune 10, 2020 at 11:32 pm

    I have used Metformin for about a decade. Last July I was diagnosed with breast cancer. Up until last summer there were no cases of breast cancer on either side of my family. Might I have reason to pursue legal action?

  • JoseJune 10, 2020 at 6:40 pm

    been taking metformin for years and stoped using six month ago due to terminal liver cancer stage4, I would like be included on this class action

  • GregJune 4, 2020 at 8:28 pm

    Have taken metformin for years now have stage 4 pancreatic cancer

  • LynnaMay 29, 2020 at 1:16 pm

    I had to undergo a hysterectomy in November of 2017 due to uterine cancer. At the time I had taken both metformin and Zantac. So, was my cancer the result of one or the other? Possibly both. I almost bled to death before the cancer was found.

  • brendaMay 21, 2020 at 5:17 pm

    my husband was prescribed metformin 3 years ago after having a severe infection in his foot due to a cut. I asked the doctor on numerous occasions to take him off because of the warning of it may cause cancer. Doctor refused. My husband was hospitalized this December due to liver/kidney failure caused by drugs?? or cancer?? All test results left a large gray answer as to the cause. My husband pa[Show More]my husband was prescribed metformin 3 years ago after having a severe infection in his foot due to a cut. I asked the doctor on numerous occasions to take him off because of the warning of it may cause cancer. Doctor refused. My husband was hospitalized this December due to liver/kidney failure caused by drugs?? or cancer?? All test results left a large gray answer as to the cause. My husband passed away early Feb. I'd like to find out the answer to insure this never happens again.

  • ThomasMay 4, 2020 at 9:10 pm

    I have been on Metformin for about 5 years now. The Start of this year 2020, i was Diagnosis with Stage 2 Rectal Cancer. I am not sure if taking metformin for many years would of caused me to have Colon cancer. My Family history, No one has had cancer. Well, My father died of lung Cancer but he was a smoker for over 40 plus years. Would I have a case?

  • RobertApril 21, 2020 at 9:45 pm

    I've been taking metformin since 2001, do I have a claim with out a diagnosis?

  • YvetteApril 2, 2020 at 5:39 pm

    what about the Veterans with Diabetes my husband's whole family has been taking this medication for years.. Who will compensate them????

  • RobertMarch 29, 2020 at 3:02 pm

    I believe users of Metformin need compensation immediately

  • AnnMarch 10, 2020 at 6:43 pm

    My husband took perscription Tagament for years and passed in 2011. I currently take perscription Metformin and have for years.

Share Your Comments

I authorize the above comments be posted on this page*

Want your comments reviewed by a lawyer?

To have an attorney review your comments and contact you about a potential case, provide your contact information below. This will not be published.

NOTE: Providing information for review by an attorney does not form an attorney-client relationship.

This field is for validation purposes and should be left unchanged.

More Top Stories