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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.

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.

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.

https://www.healthline.com/health-news/fda-investigates-if-cancer-causing-chemical-is-in-metformin