After testing showed that the N-nitrosodimethylamine (NDMA) impurity found in some ranitidine products increases over time and when stored at higher than room temperatures, FDA announced on April 1, 2020 that the agency is requesting manufacturers withdraw all prescription and over-the-counter (OTC) ranitidine drugs from the market immediately.
“We didn’t observe unacceptable levels of NDMA in many of the samples that we tested. However, since we don’t know how or for how long the product might have been stored, we decided that it should not be available to consumers and patients unless its quality can be assured,” said Janet Woodcock, director of the FDA’s Center for Drug Evaluation and Research. “The FDA will continue our efforts to ensure impurities in other drugs do not exceed acceptable limits so that patients can continue taking medicines without concern.”
In recent months, multiple manufacturers issued recalls due to unacceptable levels of NDMA.
NDMA, a probable human carcinogen, was found in ranitidine through independent laboratory testing in the summer of 2019. Low levels of NDMA are found in food and water but are not expected to lead to an increase in the risk of cancer. Sustained higher levels may increase the cancer risk.
Initial FDA tests found low levels of NDMA in ranitidine. Lacking sufficient scientific evidence to recommend use or discontinuation of the drug, FDA instead warned of potential risks and suggested the public consider alternative treatments in September 2019. Recent FDA testing— prompted by information from third-party laboratories—shows the age and storage conditions of ranitidine products may increase the level of NDMA to above the acceptable daily intake limit.
FDA testing confirmed that NDMA levels increase in ranitidine under normal storage conditions and can increase significantly in samples stored at higher temperatures. The testing also showed that for older ranitidine products, the level of NDMA is greater.
FDA said it is sending letters to ranitidine manufacturers requesting they withdraw their products from the market and is advising consumers taking OTC ranitidine to stop taking any tablets or liquid and dispose of them properly following the packaging insert or FDA’s recommended steps. During the COVID-19 pandemic, patients should not take medicines to a drug take-back location, FDA said in the statement.
Patients taking prescription ranitidine should speak with their healthcare professional about other treatment options before stopping the medicine.