FDA urges tossing of Zantac over risk of toxin’s buildup

The Food and Drug Administration on Wednesday asked companies to stop selling all forms of the heartburn drug, Zantac, after concluding that a potential cancer-causing contaminant can build up in the drug when stored for long periods.

The agency also recommended that consumers who use over-the-counter forms of the drug, also known as ranitidine, stop taking it and that they should dispose of any tablets or liquid that they have. People who take prescription forms of the drug should speak with their doctors about other options before stopping treatment.

Most manufacturers withdrew their products from the market several months ago, after an outside pharmacy raised the alarm about the drug last year. Large pharmacy chains, including Walgreen, Rite Aid and CVS, had also removed all of the products from their shelves.

The FDA said in September that the contaminant was a type of nitrosamine called N-nitrosodimethylamine, or NDMA, which is believed to be carcinogenic in humans and is found in a variety of products, including cured meats.

In a statement, Sanofi, the manufacturer of the brandname version of Zantac, said that it recalled the product in October, and that all retailers and consumers were previously instructed to return or destroy the product.

“We take this issue seriously and continue to work closely with the FDA to evaluate any potential safety risks associated with Zantac,” the company said. “At Sanofi, we stand by the long-standing science that supports the safety of Zantac OTC products, which have been used by consumers for over two decades.”

The FDA’s investigation was prompted by the findings of an online pharmacy, Valisure, which had petitioned the agency to request a recall of all products containing ranitidine because it said its own tests had revealed high levels of NDMA, above the FDA’s acceptable daily limit.

“We’re very happy about the fact that our laboratory testing has had such an impact, and we strongly support and applaud the FDA’s decision,” said David Light, a founder and chief executive of Valisure.

The problem with ranitidine surfaced last spring, when Valisure, which tests the drugs it sells for quality, began analyzing its products for the contaminant.

At the time of its testing, Valisure speculated that the source of the contaminant was the result of the “inherent instability” of the ranitidine molecule, which can degrade under certain conditions, such as high temperatures, to create the contaminant.

The FDA last year said patients could continue taking the medications and did not face health risks from low levels of a “probable” cancer-causing contaminant found in multiple brands.

But officials reversed that decision, saying they’ve now determined that levels of the chemical increase over time, especially if tablets and capsules are stored at higher temperatures. That poses an unacceptable risk to patients, they said.

Light said Valisure is researching what the long-term effects of taking the drug might be.