Nearly two months after issuing a contaminated Zantac warning, the U.S. Food & Drug Administration (FDA) is now asking pharmaceutical companies to test all lots of ranitidine-containing products for the presence of N-nitrosodimethylamine (NDMA) – a probable human carcinogen.
The FDA first warned of potentially contaminated Zantac on September 13th, after the online pharmacy Valisure informed the agency that it had detected NDMA in every sample of Zantac and ranitidine it tested, and often at levels that far exceeded the FDA’s recommended daily limits.
While Valisure maintains that NDMA in Zantac resulted from the instability of the ranitidine molecule, which may degrade when subjected to conditions similar to digestion, the FDA has yet to conclude that ranitidine actually produces NDMA in the stomach.
The FDA had previously asked drug manufacturers to submit samples for testing. But on December 4th, the agency requested they test all Zantac and ranitidine lots before making them available to consumers.
“If testing shows NDMA above the acceptable daily intake limit (96 nanograms per day or 0.32 parts per million for ranitidine), the manufacturer must inform the agency and should not release the lot for consumer use,” the FDA said.
Zantac and generic versions of ranitidine are used by millions of people to treat heart burn symptoms, GERD, and other acid-related stomach issues.
NDMA is a known environmental contaminant and found in water and foods, including meats, dairy products, and vegetables. Animal testing suggests exposure to high levels may be associated with an increased risk of cancer, and the U.S. Environmental Protection Agency considers NDMA a probable human carcinogen.
So far, the FDA hasn’t asked drug makers to conduct a Zantac recall, but several, including Sanofi-Aventis, GlaxoSmithKline, and Dr. Reddy’s Laboratory, among others, have decided to remove their ranitidine products off the market.
CVS, Walmart, Rite-Aid and other retailers have ended sales of the drugs.
The FDA has urged consumers using over-the-counter versions of Zantac and ranitidine to consider switching to an alternative heart burn treatment. To date, the agency’s testing has not found NDMA in Pepcid (famotidine), Tagamet (cimetidine), Nexium (esomeprazole), PrevAcid (lansoprazole), or Prilosec (omeprazole).
Patients prescribed Zantac or ranitidine should not stop taking the drug until they speak with their doctor, as stopping prescription treatment could cause their condition to worsen.
Anyone who continues taking either prescription or over-the-count Zantac/ranitidine should limit their intake of nitrite-containing foods (processed meats) and preservatives like sodium nitrite.