WASHINGTON, D.C. — On Wednesday the U.S. Food and Drug Administration ordered that manufacturers immediately halt distribution of ranitidine drugs, commonly known under the brand name Zantac.
The FDA said that this was part of an ongoing investigation into the drug over a contaminant called N-Nitrosodimethylamine (NDMA) in ranitidine medications.
"The agency has determined that the impurity in some ranitidine products increases over time and when stored at higher than room temperatures and may result in consumer exposure to unacceptable levels of this impurity," the FDA said in a statement.
Ranitidine products will not be available for prescription or over-the-counter use in the U.S. for the foreseeable future while the investigation continues.
According to the World Health Organization (WHO), NDMA can occur in drinking water through industrial waste or pesticides, and is "probably carcinogenic to humans," increasing the risk of cancer. Studies have yet to definitively quantify the risk of cancer from NDMA.
The FDA said that testing prompted by information from third-party laboratories confirmed that NDMA levels increased in ranitidine even under normal storage conditions, and NDMA has been found to increase significantly in samples stored at higher temperatures — including temperatures the product may be exposed to during distribution and handling by consumers.
The testing also showed that the older a ranitidine product is, or the longer the length of time since it was manufactured, the greater the level of NDMA. Those conditions could raise the level of NDMA in the ranitidine product above the acceptable daily intake limit.
— U.S. FDA (@US_FDA) April 1, 2020