NDMA led to the 2019 recall of ranitidine products, including Zantac.
N-nitrosodimethylamine, commonly abbreviated NDMA, is a chemical classified as a probable human carcinogen. Testing found that some ranitidine medicines could contain NDMA, and the amount could increase over time or under certain storage conditions. Regulators therefore asked manufacturers to withdraw products while the issue was investigated.
Ranitidine was an H2-receptor antagonist used to reduce stomach acid and treat conditions such as heartburn and ulcers. The recall affected prescription and over-the-counter products in several countries, although regulatory actions and timelines differed.
NDMA is not the same contaminant involved in every medicine recall. It was also associated with later concerns about some lots of other drugs, including valsartan, but those events involved different active ingredients and manufacturing investigations. Ranitidine products were subsequently withdrawn from many markets.