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  • Merck & Co. has discovered that nitrosamines are contaminating their diabetes medications, Januvia and Janumet. They believe they can fix the problem by the end of this year.
  • Certain nitrosamines can lead to cancer if people are exposed to high quantities.
  • The FDA has put regulations in place allowing for 37 nanograms of nitrosamine per day.
  • Other prescription and over-the-counter medications affected include losartan, metformin, ranitidine, and varenicline.

The pharmaceutical company Merck & Co. has found why their diabetes medications Januvia and Janumet has been contaminated with the cancer-causing chemicals nitrosamines, according to reports.

After discovering the reason why nitrosamines were present in the drugs, Merck sent a report to the FDA, according to Bloomberg. Reportedly, they believe they can correct the issue by the end of 2023.

The contamination was believed to have occurred primarily during storage, and also manufacturing.

As a result, Merck has improved its quality control processes in order to continuously reduce the contamination levels in the medications. The timing for when the drugs will be available will depend on FDA feedback.

“Nitrosamines are chemicals that are found in foods, cosmetics, and toys. Nitrosamines are also found in drinking water,” Kelly Johnson-Arbor, MD, FACEP, FUHM, FACMT, a medical toxicology physician and director at National Capital Poison Center, told Healthline. “Some nitrosamines may cause cancer when people are exposed to high amounts of them for a prolonged period of time.”

Because of this, the FDA established limits for nitrosamines in medications in 2020.

People who take nitrosamine-contaminated medications on a regular basis for years and years may be at increased risk for developing cancer and other unwanted health conditions, Johnson-Arbor added.

However, Merck was allowed to continue selling Januvia and Janumet in order to avoid medication shortages, according to Bloomberg.

Experts advise speaking to your healthcare provider before ending any prescribed medication.

Specifically, the chemical Nitroso-STG-19 (NTTP), a nitrosamine, was found in Merck’s medications Januvia and Janumet.

“As a class of organic compounds, nitrosamines have been in our consumptive diets for decades since they are used as food preservatives and curing agents for meats,” said Dr. Adeel Khan MPH MS, a hematologist/oncologist and assistant professor at the University of Texas Southwestern Medical Center in Dallas, Texas. “Nitrosamines are found naturally as well as from man-made manufacturing and agricultural processes.

The concern surrounding them involves their linkage to cancer. It is believed roughly 75% of nitrosamines are carcinogenic to mammals when in high enough amounts over extended periods.

Nitrosamines have been linked to malignancies such as esophageal cancer, liver cancer, stomach cancer, kidney cancer, and others.

One of the most well-studied nitrosamines, N-nitrosodimethylamine (NDMA) is tied to colorectal cancer.

Furthermore, some of the most carcinogenic (cancer-causing) nitrosamines are found in tobacco products and are believed to be highly responsible for lung cancer, Khan added.

Other medications were also affected.

“In recent years, nitrosamines have been found in many prescription and over-the-counter medications including losartan, metformin, ranitidine, and varenicline,” said Johnson-Arbor.

“At a molecular level, nitrosamines cause DNA damage through two processes, alkylation and adduct formation. Over the long run, the accumulation of DNA damage raises the risk for cancers,” said Khan.

The FDA allows for 37 nanograms of nitrosamine consumption per day and anything beyond that is potentially problematic.

Merck has recently found the cause of what is contaminating their diabetes medications, Januvia and Janumet: nitrosamines. Consequently, they are working to improve quality control and anticipate the issue will be resolved by the end of this year.

If people are exposed to high amounts of nitrosamines for prolonged periods of time, it can increase their risk of cancer. The reason is because nitrosamines cause DNA damage.

There are additional prescription and over-the-counter medications that have been contaminated which include losartan, metformin, ranitidine, and varenicline.