(WTAJ/CBS) — There are new concerns about the popular heartburn drug ranitidine and a chemical linked to cancer.
The initial findings last September spurred a partial voluntary recall of Zantac and its generic versions, taken by an estimated two million Americans.
Dr. Jon Lapook looks inside the lab that has uncovered the latest concerning findings.
At Emery Pharma in California, Chemist Ron Najafi has been trying to figure out why FDA testing revealed some batches of ranitidine had unacceptable levels of NDMA, a chemical linked to cancer.
At room temperature, a standard dose of ranitidine rose to 25 nanograms of NDMA below the FDA daily acceptable limit of 96. But when ranitidine was heated to a hundred and 58 degrees, the level rose to 142 nanograms.
“So if someone were to keep their ranitidine, Zantac, in their car for example, and in the middle of summertime, that product is going to get heated up and it’s going to generate this carcinogenic compound, so NDMA in this case, Jon, is not an impurity in the drug, it’s being formed from the drug itself.,” Ron Najafi: CEO Emery Pharma.
He’s now serving as an expert witness for plaintiffs in litigation involving NDMA.
Request a recall of all ranitidine products, require the medicine to be shipped under controlled temperatures, and order further testing to assess stability.
Dr. Janet woodcock heads up drug evaluation and research at the FDA.
“It does appear when ranitidine is heated significantly that there is conversion into, some NDMA can form, however, these are pretty high temperatures, so question about whether ranitidine would need to be kept cold to keep it from converting is something that still hasn’t been answered,” said Dr. Janet Woodcock: FDA Center for Drug Evaluation & Research Director.
Dr. Woodcock said the FDA is still investigating why some batches contained higher levels of NDMA than others.
“For most of these contaminants that we are talking about, the level of NDMA or other nitrosamines in there is not much more than what you might get in your ordinary daily diet, especially if you ate a lot of meat,” said woodcock
Since the recall is voluntary, the f-d-a says there still may be some ranitidine product on store shelves.
Sanofi tells CBS news testing of its brand-name Zantac products is ongoing, and for now, it has pulled the medication from store shelves.
Many companies selling generic forms of the pill have done the same.
As for the source of the NDMA, the FDA says the investigation is ongoing.
They do not think it’s an impurity added in the production process.