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Breaking Health News | Metformin and Nitrosamines!

Some countries are recalling the popular diabetes drug metformin. That's because of concerns about metformin and nitrosamines. Nitrosamines are nasty!
Recall stamp illustration isolated on white background.

Not again! Another nitrosamine scare has just been announced for one of the most popular drugs in the pharmacy. Metformin is the number one most prescribed diabetes drugs in the U.S., if not in the world. At last count, 18 million citizens filled 89 million prescriptions for metformin last year. But word from abroad, and now from the FDA, suggests that there is a concern about metformin and nitrosamines. 

What Are Nitrosamines?

For the last year and a half, you have been reading about blood pressure medicines that have been contaminated with nitrosamines. Millions, perhaps tens of millions, of pills have been recalled. We’re talking about drugs like irbesartan, losartan and valsartan. Then there was the ranitidine (Zantac) recall. That was also because of nitrosamines. We have lost count of how many recalls have occurred over the last year or so. 

Nitrosamines are potent cancer causing chemicals. In recent news stories journalists have taken to calling compounds like NDMA “probable carcinogens.” We think that is way too cautious. Here is what the American Chemical Society stated about nitrosamines in 1979:

“Among carcinogens the N-nitroso compounds are the most broadly acting and among the most potent.”

N-nitroso compounds include nitrosamines. Animal studies demonstrate that most nitrosamines induce tumors in rodents. We have no reason to suspect that humans are immune.

The FDA keeps reassuring the public that the levels of nitrosamines in drugs like ranitidine or metformin are low and not worrisome. The trouble is that there have been no well-controlled human trials to determine if that is really the case. Such studies would cost hundreds of millions of dollars and take decades to complete. We may never know how many people were harmed by nitrosamines in losartan, valsartan or ranitidine. Most people would prefer not to swallow any dose of nitrosamines with their medicine every day for years.

Metformin and Nitrosamines?

The breaking news about metformin and nitrosamines came in just as we were completing an article about how the FDA Embraces Generic Drugs from India Despite Quality Problems. We have provided detailed information about the metformin and nitrosamines controversy in that article. Rather than repeating everything here, we suggest you go to that article in the newsletter for all the details. Here is a link

The executive summary is as follows:

Valisure, a pharmacy in New Haven, CT. has been testing all the pharmaceuticals it sells for quality, purity and nitrosamines. It was Valisure that notified the FDA there was a problem with ranitidine. We spoke with the CEO this afternoon and he alerted us to the fact that his testing lab detected nitrosamines in samples of metformin from abroad. 

In addition, the FDA put out a statement Thursday evening that:

“While we are aware that some regulatory agencies outside the U.S. may be recalling some metformin drugs, there are no metformin recalls affecting the U.S. market at this time.”

Are you reassured? Once again the FDA seems to be moving very cautiously, just as it did with the ranitidine and valsartan nitrosamine recalls. You can read more about that process at this link:

Valsartan Blood Pressure Pills Recalled over Cancer Concerns

We would not be surprised to learn in a week or two or three that the FDA has discovered metformin and nitrosamines are a concern. The Food and Drug Administration has a very hard time admitting that it ever makes mistakes. If drugs are found to be contaminated with impurities, it reflects badly on the agency. We keep being reassured that the United States has the best and safest drugs in the world. After so many recalls, we are beginning to wonder if the FDA really has its monitoring act together.

Read more about the latest breaking health news regarding metformin and nitrosamines at this link. You will learn about how you can have your pills tested. You will get an overview of the FDA position on metformin and nitrosamines. Do not stop taking metformin suddenly! Controlling blood sugar is essential.

Are you getting fed up with all the recalls? Share your thoughts in the comment section below.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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comments (21 total)
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Valisure is making itself an indispensable national asset. I certainly have more confidence in them than I do the FDA. I think we have to question who the FDA is working for and why they are so timid in doing their job.

For me, what really makes me angry is that we have no way to know where our drugs are manufactured. When I expressed my concern to my pharmacist over the Losartan I was taking, he said, “You’re probably fine.” THAT’S your response? He told me they have no way to know what manufacturer’s pills went into which bottle. How is that possible? We can track packages to the point of showing a photo of the delivery point, but you can’t scan a bar code from a package into my records, so you could track my drugs? That’s ridiculous. And scary as hell.

So, now what should those of us taking metformin do? I am on 500 mcg 2 AM & 2 PM and just ordered a 30-day refill !

Wait to see what the FDA announces. It is doing testing right now. Perhaps the levels of nitrosamines will be so low as not to pose a problem. We will have to see what the agency recommends.

I recently called my Medicare D by-mail prescription supplier when I noted they had switched from a U.S. manufacturer of Valsartan to an India manufacturer of Valsartan after the recall had been in effect. They indicated this new (India) supplier was safe. Why did they even have to switch from a U.S.-based manufacturer, especially after there had been a recall?

Now I have to worry about the Metformin I take, too? They’re not even indicating on the bottle where the drugs are from.

Are India and China trying to kill us with the FDA’s blessing?

I switched to Glumetza as the brand instead of the generic Metformin and am wondering if this medicine also contains nitrosamines or is it just in the generic?

Also, I switched from Losartan to Diovan and wondering the same thing – are the brand nitrosamines safe?

I think it is about time that a plan be put in place to have drugs that are bought and sold in America, be made in AMERICA where they can be monitored and managed properly. The FDA has no control over any of the companies overseas that produce and make our drugs. No surprise visits to check exactly what the conditions and the environment are in the plants that produce the medicines. I know this cannot be done overnight, but it needs to be looked into and started now.

So tired of poor FDA stating tainted drugs are ok for use. The FDA needs to be restructured from the top down, more agents who check out of country manufacturing plants need to be hired, and in a timely fashion.

People have no other options but to take potentially tainted drugs as pharmacies are instructed by the FDA which drugs are no longer safe.

For those of us that have taken these affected drugs, what are we to do? I guess our lives are not important.

I am not on metformin however I still take Valsartan and I also take Zantac very often. Quite a few people I know were switched from Vasartan to Losartan – we know how that went! My valsartan is now from a company not on ‘the list’ As for Zantac, I don’t care to change to another brand which will probably then be in the news also for nitrosamines. I feel it is a shame that the stores pulled Zantac from the shelves when nothing was actually proved. There is not an actual recall and I hope by the time i finish my bottle of 80 that this blows over and it is back in the stores. Yes, fed up to be expected to constantly seek new brands.

Public expects more and stricter standards
For too long lax procedures and excuses have predominated.

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