Is there a cancer-causing chemical lurking in your medicine? There is for millions of people who take popular drugs such as Valsartan (blood pressure), Metformin (diabetes) and Zantac, which was recalled earlier this year because of this looming threat to human health.
The potentially-deadly substance is called “NDMA.” (Not to be confused with the party drug MDMA, aka “ecstasy.”) NDMA is a nitrosamine, which is a group of chemical compounds. Most nitrosamines are carcinogenic.
Trace amounts of NDMA float in the air you breathe, as well as in drinking water. The compound is also formed in fried foods, cured meats and other foods that contain nitrites. Nitrites convert into nitrosamines. Another source of nitrosamines is soil fertilizer, where nitrites can leach into potatoes and other food crops.
But perhaps the biggest risk of nitrosamine exposure is through certain prescription drugs. NDMA contamination in medicine has become enough of a problem that the Food and Drug Administration last month issued a 24-page guidance on how drug manufacturers can detect and prevent NDMA contamination.
The guidance includes conditions that give rise to nitrosamine impurities such as NDMA. (In addition to NDMA, other nitrosamine impurities include NDEA; NMBA; NMPA; NIPEA; and NDIPA.)
The FDA describes NDMA and other nitrosamine impurities as “probable human carcinogens.” How prevalent is the cancer-causing compound in drugs? That question has yet to be determined. Which is why in the guidance, the FDA cautions, “Although nitrosamine impurities have been found in only some drug products, and batches of those products have been recalled when there were unacceptable levels of these impurities, nitrosamine impurities might exist in other [active pharmaceutical ingredients] and drug products due to use of vulnerable processes and materials that may produce nitrosamine impurities.”
In other words, every prescription drug that contains synthetic active ingredients are at risk of NDMA contamination. The health threat of dangerously-high levels of NDMA was noticed just two years ago, when the FDA was alerted about the contamination in Valsartan, an ARB drug (angiotensin II receptor blocker) used to treat high blood pressure.
In September 2019, popular heartburn remedies made with the active ingredients ranitidine (Zantac) or nizatidine (Axid) fell under the FDA’s radar. These drugs were found to contain unacceptable levels of NDMA. After a recommendation by the FDA, manufacturers of these drugs voluntarily recalled ranitidine and nizatidine products.
The FDA determined that NDMA levels in ranitidine products stored at room temperature can increase with time to unacceptable levels. After further FDA testing revealed elevated levels of NDMA measured in all ranitidine products after just two weeks, the regulatory agency requested on April 1 of this year that all ranitidine products be withdrawn from the U.S. market.
According to DrugWatch.com, FDA identified other conditions under which nitrosamines can contaminate medications: chemical reactions that occur when using recovered chemicals, contamination from vendor-sourced raw materials, inadequate purification and lack of process control and optimization.
DrugWatch also lists the number of lawsuits pending in federal courts over certain NDMA-contaminated drugs. To date, there are 500 Zantac lawsuits and 600 Valsartan lawsuits.
The FDA is not sure how long ago NDMA contamination started to become a problem. The number of people at risk of developing cancer from these tainted drugs could be in the thousands. And for the untold scores of people who have developed cancer, at least in part because of NDMA contamination, the guidance comes too late. Consequently, the number of lawsuits against manufacturers of NDMA-contaminated drugs is expected to skyrocket.